tll hoc h6a
•
•
KEM - TQp ch( Olympiad H6a h<;>c
'
.,
�
LOI MO DAU
Ouy d9c gia than men, trong qua tr1nh bien djch de thi Olympiad quoc te (lchO) va cua cac
quoc gia khac, chung t6i nh<;in thay c6 SI/ chenh l�ch tvong doi Ion ve SI/ c<;ip nh<;it kien thCrc
trong cac de thi cua Vi�t Nam va the gibi. Nham dap Crng nhu cau cua giao vien va h9c sinh
chuyen trong vi�c tiep c<;in voi nhC!ng nguon kien thCrc h6a h9c hi�n d<;ii hon, ban bien t<;ip t<;ip
chl KEM do bien soc;m b9 tai li�u Tl/ h9c Hoa (mo: THH181, dvqc chia thanh 9 tuyen t<;ip gom: 1)
Cau t<;io chat; 2) Vo co; 3) Nhi�t d9ng; 4) 09ng h9c; 5) Phan tkh - Oi�n h6a; 6) Co che phan
Crng; t) Tong hqp HC!u co; 8) Xac djnh cau true hqp chat hC!u co; 9) Tuyen t<;ip de thi thll HSGQG
OlympiaVN (tu nam 20lt do doi ten thanh OCC - OlympiaVN Chemistry Challenge). N9i dung
cua moi quyen sach trong tuyen t<;ip nay la 100 bai t<;ip (kem loi giai chi tietl dvqc ch9n l9c tu
cac tai li�u dung cho boi dvong h9c sinh di/ thi Olympiad cua Trung Ouoc, Nga va cac bai
giang Advanced Chemistry tu nhieu trvong 8Qi h9c hang dau nvoc My.
Do SI/ chuan bi gap rut va m9t so h<;in che trong vi�c djch thu<;it (SL! dl,mg nhieu nguon tai li�u
ngoai tieng Anh) nen c6 the van con nhCmg loi sai ho(lc thieu sot. Mong quy d9c gia quan tam
c6 the glli phan hoi ve dja chi: tapchikem@gmail.com. Chan thanh cam on.
2
ML.JC IL_JC
J\nh sang va v�t ch�t - Nang hrq-ng vi h�t................................................................................................................... 7
Bai J - Anh sang va vi;U chiit .....................................................................................................................................7
Bai 2 - B(rc x� di�n n'r ...............................................................................................................................................9
Bai 3 - S6ng ............................................................................................................................................................ 11
Bai 4 - H
. i�u (rng quang di�n ...................................................................................................................................14
Bai 5 - Hi�u frng quang di�n ...................................................................................................................................17
Bai 6 - Nang luc_yng ion hoa .....................................................................................................................................20
Bai 7 - Cong th(rc de Broglie ..................................................................................................................................21
Bai 8 - Cong th(rc de Broglie ..................................................................................................................................23
Bai 9 - fl(\ng nang va ct9ng ltrc_yng ........................................................................................................................... 26
Bai 10 - Cong th(rc Rydberg cho nguyen tir hydrogen............................................................................................ 28
Bai I J - S6 song ...................................................................................................................................................... 30
Bai 12 - Ph6 hydrogen ............................................................................................................................................31
Bai 1. 3 - Ph6 ct'ta hydrogen ......................................................................................................................................33
Bai 14 - Ph6 ct'ia nguyen tir hydrogen ..................................................................................................................... 35
C�u hinh electron....................................................................................................................................................... 38
Bai 15 - Cac s6 luc_yng tir .........................................................................................................................................38
Bai 16 - Nguyen n'r nhi�u electron .......................................................................................................................... 40
Bai 17 - Nguyen n'r nhi�u electr on ..........................................................................................................................41
Bai 18 - Ciiu hlnh electron ......................................................................................................................................42
Bai J 9 - Nang luc_yng lien k�t electron ..................................................................................................................... 43
Bai 20 - Nang brc_yng ion h6a ...................................................................................................................................45
Bai 21 - Phuong pbap Slater ...................................................................................................................................46
Bai 22 - Phuong pbap Slater ...................................................................................................................................47
Bai 23 - Nang luc_yng ion h6a ...................................................................................................................................48
Bi�n d6i ooh ch�t trong bang tu� hoan ................................................................................................................. 50
Bai 25 - Bang tu�n hoan n16-i (I) ............................................................................................................................. 50
Bai 26 - Bang tu�n hoan m&i (2)............................................................................................................................. 52
Bai 27 - Bang n,� l10an m&i (3).............................................................................................................................54
Bai 28 - Bang tu� hoan 1n6-i (4) ............................................................................................................................. 56
Hoa hqc b�t nban.......................................................................................................................................................60
Bai 29 - H6a hQe h,:tt nhan ....................................................................................................................................... 60
Bai 30 - Phan ra ph6ng xc:1 ....................................................................................................................................... 62
Bai 31 - H6a hQe h:;tt nhan ....................................................................................................................................... 64
Bai 32 - H6a hQe h,:tt nhan ....................................................................................................................................... 65
Bai 33 - Phan ra ph6ng xc:1-....................................................................................................................................... 67
Bai 33 - Phan ra ph6ng xc:1-....................................................................................................................................... 69
Bai 34 - Phan ra ph6ng xc:1-....................................................................................................................................... 71
Bai 35 - Phan ra ph6ng Xi;t....................................................................................................................................... 74
Bai 36 - Phan ra ph6ng xi;,........................................................................................................................................ 77
Bai 37 - Phan ra ph6ng xi;,. ......................................................................................................................................78
Bai 39 - Phan ra ph6ng xc:1........................................................................................................................................ 79
Bai 40 - Phan ting h,:tt nhan tren m�t troi ................................................................................................................ 85
C�u true phan tfr · Thuy�t MO ................................................................................................................................87
Bai 41 - L\te lien k�t ............................................................................................................................................... 87
Bai 42 - Nang lugng lien k�t ................................................................................................................................... 88
Bai 43 - Nang hrgng lien k�t ................................................................................................................................... 89
Bai 44 - Mo1nent quan tfnh ..................................................................................................................................... 90
Bai 45 - Cilu true phan tfr ........................................................................................................................................92
Bai 46 -Thuy�t VSEPR .......................................................................................................................................... 93
Bai 47 -Thuy�t YSEPR .......................................................................................................................................... 95
Bai 48 -Thuy�t YSEPR .......................................................................................................................................... 96
Bai 49 -Thuy�t YSEPR ..........................................................................................................................................98
Bai 50 - Thuy�t YSEPR ........................................................................................................................................ 10 J
Bai 5 l - S\r lai h6a ................................................................................................................................................ l 02
Bai 52 - C�u true phan tt'r ...................................................................................................................................... 103
Bai 53 -Thuy�t MO ..............................................................................................................................................105
Bai 54 -Thuy�t MO .............................................................................................................................................. I 07
Bai 55 -Thuy�t MO .............................................................................................................................................. 108
Bai 56 -Thuy�t MO .............................................................................................................................................. I 09
Bai 57 -Thuy�t MO .............................................................................................................................................. 110
4
Bai 58 -ThuyBt MO .............................................................................................................................................. J J 2
Bai 59 -ThuyBt MO .............................................................................................................................................. 114
Bai 60 -Thuy�t MO .............................................................................................................................................. 117
Bai 61 - B�c lien k�t .............................................................................................................................................123
Bai 63 - B�c lien k�t ............................................................................................... Error! Bookmark not defined.
Bai 64 - B�c lien k�t .............................................................................................................................................124
Bai 65 - Bi)c lien k�t .............................................................................................................................................125
Bai 66 - B�c lien k�t ............................................................................................................................................. 126
Bai 67 - Bijc lien k�t .............................................................................................................................................127
Bai 68 - ThuyBt MO .............................................................................................................................................. J 29
Bai 69 -Nang lugng ion h6a phan tir ....................................................................................................................130
Hoa hrcyng tir ............................................................................................................................................................ 131
Bai 70 - HQp thB 11191 chi�u ................................................................................................................................... 131
Bai 71 - H9p thB 1n9t chi�u ................................................................................................................................... J 35
Bai 72 - H6a hQc lugng tfr kha kiBn ...................................................................................................................... I 38
Bai 72 - Hi)p thB 1119t chi�u ................................................................................................................................... J 41
Bai 73 - Hi)p th� 11191 chi�u ................................................................................................................................... 145
Bai 74 - H9p thB m9t chi�u ................................................................................................................................... 146
Bai 75 - H9p thB 11191 ch.i�u ................................................................................................................................... J 48
Tinb th�..................................................................................................................................................................... 150
Bai 76 - Cfiu true hai chi�u ................................................................................................................................... 150
Bai 77 - Tinh th� kim lol1ti ..................................................................................................................................... IS I
Bai 78 - Tinh thS kim lo�i .....................................................................................................................................153
Bai 79 -Tinh thS plantinum ..................................................................................................................................154
Bai 80 -Tinh th� nhon1 ......................................................................................................................................... J 55
Bai 81 -Tinh th� si!icon ........................................................................................................................................ I 56
Bai 82 -Tinh th� titanium .....................................................................................................................................157
Bai 83 -Tinh thS titanium.....................................................................................................................................158
Bai 84 - Tinh th� sodium ...................................................................................................................................... 159
Bai 85 -Tinh th� tantalum .................................................................................................................................... 160
Bai 86 - Tinh th� nickel ........................................................................................................................................ 161
5
Bai 87-Tinh thA lithium.......................................................................................................................................162
Bai 88-Tinh thA thi&: xam ................................................................................................................................... 163
Bai 88a -Hftp th\l hydrogen .................................................................................................................................. 165
Bai 89 -HQ'p kim Cu-Zn ....................................................................................................................................... 168
Bai 90 - Nhi�u X<;l tinh thA .....................................................................................................................................169
Bai 9 l - Nhi�u X<;l tinh th8 ..................................................................................................................................... l 70
Bai 92 - Nhi[u X<;l tinh th! ..................................................................................................................................... 171
Bai 94 - Nhi�u X(:I. tinh th! ..................................................................................................................................... 172
Bai 95 - Nhi�u X(:I. tinh th! ..................................................................................................................................... 173
Bai 96 - S\r t(:10 thanh epitaxy ................................................................................................................................ J 75
Bai 97 - V�t li�u sieu dful ......................................................................................................................................177
Bai 98 - Carbide kin, lo<;li ......................................................................................................................................179
Bai 99-Cftu true tinh thB die hQ'p chftt silicon ..................................................................................................... 182
Bai 100-C�u true tinh thS .................................................................................................................................... J 84
Bai 101 - Nang luQ'ng ITI<;lllg luoi .......................................................................................................................... 185
Bai J 02 -Nang luQ'ng n1c:u1g luoi .......................................................................................................................... 187
Bai I 03 -Nang hrQ'ng 1nc:u1g luoi .......................................................................................................................... 188
Bai 110 - Cfu.t true tinh thA ion .............................................................................................................................. 189
Bai 104-Tinh thA NaH ......................................................................................................................................... 191
Bai 105 -Tinh th� ion ........................................................................................................................................... J 92
Bai I l I -Cllu true tinh thB ion .............................................................................................................................. 193
Bai 106 -Cftu true tinh th� ion .............................................................................................................................. 194
Bai 107 -Tinh thB oxide h6n hcrp ......................................................................................................................... 196
Bai 108 - Tinh th� nickel oxide............................................................................................................................. I 97
Bai J 09 - Tinh th� iron oxide ................................................................................................................................ J 99
6
,
,
Anh sang va vit chat - Nang ltr«yng vi h�t
,:,Tranh nhfim l§n gifra ki hi�u cua tfin s6 (v) voi v�n t6c (v ho�c u)
Bai 1 - Anh sang va v�t ch§t
1) Khi mot chum tia electron tdc do cao dtrQ'C bin vao b� m�t mot m§u rin th) hay cho bi�t tigu
phan nao se la thanh ph§n chfnh cua tia thl'.r c§p? Giai thich co ch� t�o thanh cac tigu phan
nay va sip x�p cac h�t tham do theo tlu'.r n.r dam xuyen khi brtn vao m§u rrtn va neu 1 y do.
2) MQt laze c6 nang lm;mg 0.4 J duqc t�o ra tu cac xung bl'.rc x� trong 3.0 ns (nano giay). Ttnh
cong suit do 1 xung ciia laze d6 t:;io ra.
7
HU'(mgdiin
1) Thu n,r cac h�t tham do nlm sau: photon< electron th u c�p < electron tan x� nguqc < tia X
Photon: Cac electron & l&p ngoai cung duqc kfch thfch khi chi�u Xf.l b&i tia t&i. K.hi electron
chuy�n til' tr:;ing thai kfch thfch v� tr:;ing thai ca ban. se sinh ra buc x� trong vung UV-Vis. Do kha
nang darn xuyen y�u cua tia UV-Vis nen chi quan sat duqc s\t bil't ra & b� mi;tt tinb th�.
Electron thu c�p: Nang luc,ng tu cacti.a s<J c§p se giup cho cac electron thoat ra kh6i nguyen tfr &
m§u r�n. D� duqc nlm v�y nang luQ'ng cung dp se phai l&n hon l\tc lien k�t giua electron v&i h:;it
nhan va nlnr v�y n6 phai c6 d911g nang thiip. Chi quan sat duqc cac electron thu ciip & l&p sat b�
m�t.
Electron tan x:;i nguqc: Cac ti.a electron sa c§p va ch:;im v&i nguyen ti'r trong m§u rful bfulg cac va
ch:;im dan h6i ho�c khong dan h6i. M9t s6 electron bi tan x:;i ngm;rc va c6 th� do duqc. B911g
nang cua cac electron tan x:;i ngttQ'c cao hem elechon thil' dp.
Tia X: K.hi electron & orbital l&p ben trong bi but ra b�ng cac ti.a sa c�p thl qua trlnb h6i phµc se
san sinh ra tia X. Do kha nang dam xuyen cao cua tia X thl ta c6 th� xac dinh duqc nhung S\t va
cb:;im sau ben trong va tr<;l.Ilg thai kfch thich cua m§u.
2) Cong su�t P ciia laze duqc tinh theo bi�u thirc: P;;;; E(J)/t(s) v&i E la nang lm;mg, t la th&i gian.
P = E/t = 0.40/(3· 10-9) = 1.3· 107 W;;;; 13 mW
8
Bai 2 - Btrc x� di�n ti'r
v/Ht
-.. >... :5
M1cro1,1, 11vc11:
R1d10
!?
Shor1wovc r:id10
WIIVCS
10
4
I0
1
X niys
y rays
C
TV
10•
u
� �
.0
10
2
I 0•
4
"
,o-
10·•
l/m
Cac vung btrc x� di�n tir.
(Chu thfch: radio wave= s6ng vo tuy�n; shortwave= s6ng ngiin; microwave= vi s6ng; infrared
= h6ng ngo:;ii; v isible= kha kj�n; ultraviolet= f:lr ngo:;i.i; X-ray= tia X; y ray= tia gramma.)
1) Bue x:;i, vi s6ng c6 bu&c s6ng 1.0 cm. Tfnh tfu1 s6 va nang lm;mg cua m<)t don quang fir
(photon) cua buc X'-1 nay. Ti.nh nang ltr<,Yng cua m9t s6 Avogadro photon (g<;>i la 1 einstein)
cua buc X:;t nay.
2) Bue X'-1, trong vung tll' ngo:;ti cua ph6 di�n tl'r tlnrong dtr<,YC mo ta tl1eo bu&c s6ng A, va ti.11]1 theo
nanometer (10-9 m). Tfnb cac gia tri v, v va E cua birc x:;i di�n tit c611.= 200 nm.
3) Bue X'-1 trong vung h6ng ngol;li tlnrcmg du<,Yc bi�u di�n theo s6 s6ng, v = � . M<)t gia tri v
di�n hlnh trong vung nay la 10 3 cm- 1• Tfnh cac gia tri V, A, va E cho bl'.rc X'-1, nay.
4) Di qua Vl1.ng h6ng ngo,;1i, theo lm&ng nang luqng giam d:ln, la vung v i s6ng. Trong vung nay,
bl'.rc x,;1 thm'mg dm,rc d�c tnmg bm tfu1 s6, v, bi8u di8n tl1eo don vi megahe1iz (MHz), trong d6
don vi hert (Hz) la 1 chu kl m6i giay. M◊t t�n s6 vi s6ng di8n hinh la 2.0· 104 MHz. Tfnh cac
gia tri v, A, va Echo bl'.rc X,;l nay.
9
HU'(mgdiin
1)
v=-= 3.00 x 110 mis
8
C
1.0 X 0-:? m
E
3.0 X I 0
10
6.63 x 10 - J s x 3.0 x 10 10 -1
11
hv
2.0 X 1 o-!l J _ 6.02 X I 0 11 photon
photon
mol
I
2.0 x IO 1� .J/photon
12 J/mol
2)
2.998x ,as m-s-•
= I 50 x IO') Hz
.\
200x 10-9 m
I
ii = � =
5 00x Io• cm_,
J.. 200 x 10-7 cm
_ Ire _ (6.626x 10 ,, J-s)(2.998 x 10• m•s 1) _
- 9 . 93 xi o-" J
_
E
.,
).
200 X 10 m
v = :_
=
=
3)
v
= cv = (2.998 x 101 m· _,)( Ix 10\ m- 1) = 3x I0'l Hi
I
1
5
A = -=
I = I X I0- m
ii
Ix 101 m£ = hv = (6,626 X ,o-" J-s)(3 X 10 13 Hz)= 2 X 10- 20 J
4)
Ix 106 H1.
v = 2.0x 10' MHt ( --- ) = 2.0 x 10 10 s- 1
-I MHz
C
2.998 X 106 m• -I
= 1.5 X 10-2 m
).
IO
I
V
2.0 X 10 S£ = lzv = (6.626 X 10-3'1 J-s){2.0 X 10 10 S-1) = 1.3 X IO-li J
=-=
Bai 3 - Song
1) Xet cac s6ng (wave) bi�u di�n bttc X(;l di�n tt'r sau day. Song na.o co bu&c song dai hO'n? Tin.h
cac bu&c s6ng. S6ng nao c6 tfu1 s6 va nang lm;mg photon l&n han? Tinh cac gia tri 1:trang irng
cu.a song do. S6ng nao c6 v�n t6c l&n hon? Xac dinh ki�u birc x:;i di�n tt'r ciia m6i s6ng.
---1.6 X 10 lni---
2) Mot lo:;u birc x:;i di�n tt'r (a) c6 t§n s6 107.1 MHz, mot birc x:;i khac (b) co buck song 2.12· 10-
io m va mot birc x:;i khac nfra (c) c6 cac photon mang nang lm;mg b�ng 3.97· 10- 19 J/photon.
Cho bi�t m6i hire x:;i thuoc lo:;u nao? Siip x�p chung theo thir ti,r tang d§n nang hrc:mg photon
va tang d§n dn s6.
3) Khi bi ddt n6ng, l ithium birc x:;i anh sang man do, c6 bu&c song A= 670.8nm, tuO'Ilg irng voi
bu&c chuy�n tt'r c�u hi.nh electron (ls)2(2p) 1 � (ls)2(2s) 1 . Tinh t§n s6, s6 song va nang lm;mg
theo kJ mor 1 Clla anh sang do.
JI
HU'(mgd�n
1) Bu&c s6ng la khoang each gifra cac dinh s6ng li�n nhau. Song a co 4 bu&c s6ng va s6ng b c6 8
bu&c song. Bu&c s6ng dia hai s6ng a, b l§n lm;rt la:
1.6 X I() l ITI
l
1.6 X 10 'Ill
J..
10 1m
4.0
2.0"' 10-J m
Song a co bu&c song dai hon. Do tful sd va nang luQ'Jlg photon ti 1� nghieh voi bu&e song nen
s6ng b e6 tful sd cao hon va nang lm;mg photon 16n h011 (do co bu&c s6ng ng�n hon).
"=
E
� =- 3.00 x IO� n s
A
1.5
2.0 X 10 Im
)t
Io'' s 1
= he = 6.63 x 1 0-' 1 J x 1.00 x 108 m/,
).
2 0 X IQ Im
9.9 x 10 2� J
Ca. hai song nay d�u etta bue xc;t h6ng ngo�.
2) Bue Xc;l (b) co bu&e song 2.12•10- 10 m la tia X.
Bue xc;t. (a) c6 tftn sd 107.1 MHz 1lr011g ung v&i bu&c s6ng:
). =
c = 2.9979 x IOk m/,
v
l 07.Jxl06 ,
1
2.799 m
Day la song VO tuySn.
Bite xc;t c6 nang lm;mg photon 3.97· 10· 19 I/photon tum1g irng v&i bu&c s6ng:
he = -----------6.626 x 10-)1 J s x 2.998 x 10• ml,
h= 3.97 X 10 l'I J
L
5 00
10 m
Day la anh sang kJ1a kiSn (xanh l\lC.)
Tr�t t\r nang lu<;Yng photon va din sd ti I� nghich v&i tr�t n,r bu&c s6ng.
s6ng v6 tuySn FM< anh sang kha ki�n (xanh h1c) < tia X
3)
1
=l.49lxl04 crn-t
17= ..!. =
7
A. 670.8xl0- cm
12
E = hvNA = 6.626x 10-34 J • sx4.469x 10 14 s- 1
X
6.6023x )023 mOl" 1 =} 78.4kJ · mor 1
13
Bai 4 - Hi�u ll'ng quang di�n
Hi�u ung quang di�n la hi�n tttQ'ng ma cac electron bi but ra khoi b� m{lt ctia mQt kim lo::,ii khi
anh sang chi8u vao. Anh sang phai. c6 mQt t§n s6 (nang lttQ'ng) t6i thi�u d� lo::,ii bo cac electron
khoi b� m{lt kim lo::,ii. Anh sang c6 tfi.n s6 dtt&i qrc ti�u th1 khong c6 electron nao bi birt ra, trong
klri d6 anh sang c6 tful s6 b�g ho{lc cao hO'n c\rc ti�u th} gay ra hi�n tm;mg quang di�n. V&i anh
sang c6 t�n s6 cao hO'n c\rc ti�u, nang luqng du thira duQ'c chuy�n thanh dQng nang ctia electron
thoat ra.
1) Cong thoat ctia mQt nguyen t6 la nang luqng dn d� lo:;ii 1 electron tir b� m�t r�n. Cong thoat
cu.a litlrirnn la 279.7 kJ/mol (nghia la 116 dn 279.7 kJ nang luqng d� Lo::,ii 1 mol electron khoi
1 mol nguyen tu Li tren b8 m�t kim lo:;ii Li.) Tinh bu&c s6ng C\l'C d:;ii cu.a anh sang c6 th8 lo:;ii
l electron khoi b� m�t kim lo:;ii lithium.
2) C§n 208.4 kJ nang lm:mg d� tach 1 mol electron khoi cac nguyen tfr tren b� m�t kim lo:;ii
rubidium. N8u kim lo:;ii rnbidimn duqc chi8u x:;i b&i anh sang 254 nm, tinh dQng nang clJc d:;ii
ma electron giai ph6ng c6 th� c6.
3) T§n s6 nguong cf1a kim lo::,li potasirnn la 5.464· 10- 14 s- 1. NBu su dl.lllg kim lo::,ti nay lam
cathode quang di�n thl khi chi8u anh sang tfr ngo:;ii 300 mn vao pin quang di�n thl t6c do C\l'C
d::,ii cu.a quang di�n tu la bao nhieu?
4) BiBt cong thoat (cp) Clla cluomium la 4.40 eV. Tinh dong nang Ctla electron thoat ra tir b8 mijt
chromirnn dm,rc chi8u x:;i b&i bite x:;i tu ngo:;ii c6 bu&c s6ng 200 nm.
5) Khi mot b� mijt b::,ic s:;ich duqc chi8u x:;i b&i anh sang c6 bu&c song 230 nm, dong nang cfia
electron bl'.rt ra la 0.805 eV. Tfuh cong thoat va t§n s6 nguong ctia b:;ic.
14
HU'(mgd�n
1) Nang luQ11g d.n d� lo�.i 1 electr on la:
279.7 k:J
I mol
x
1
mol
6.0221 x 10�
L
c.
4.645 x 10 "� kJ
4 645 x 10 19 J
= � \ = � = 6.6261 x 10-' 1 h x 2.9979 x 108 mis
• "'
A
E
4.645 x Io-19 J
4.277 >< 10 m
427.7 nm
2) Nang luQ'ng dn d� lo�i 1 electron la:
208A kJ
mol
--- X
l mol
n
kJ -J.461 X )Q 19 J - f:•w
.,, - 3.46) X )0
6.022 X Io·
Nang luQ'ng cua anh sang 254 nm la:
[� =
he = (6,626 x 10..J ' J '1)(2.998 x 108 rn/-;) _
7_82 x 10 19 J
A.
254 X 10 ? m
Ephoton =EK + E w, E K= 7.82• 10" 19 J - 3.461 • 10" 19 J = 4.36· 10· 19 J = dQng nang Cl,!C d�
3)
1
hv= hv0 +-mv2
?
2
2.998xl0s :•s-t
1 -1
2x6.626x10-34 J•s(
-5.464x10 4s J
300x10- m
9.109x10-3 1 kg
I
2x6.626x10-34 l •s x4.529x 10 14 s- 1 2
=[
]
9.109xl0-3 1 kg
= 8.12x 105 m•s-1
15
4)
1.602 X 10 l'I
J) = 7.05 x JO
<I> = 4.40 cV ( -----
leV
-10
J
lac
(6.626 x 10-l-• J •s) (2.998 x 10 m-s- 1)
Ji V = - = ..;_--------�- ----
A
= 9.93 X 10- 19 J
200 X 10-9 m
KE=hv-</>
= 9.93 X 10- 19 J - 7.05 X 10- 19 J = 2.88 X 10- 19 J
5) Tinh cong thoat:
tf> = hv - KE=
T - KE
nc
(6.626 x 10- 34 J•s) (2.998 x 101 m-s- 1) _ O O
1.602 x 10 19
cV
.S
S
(
230 x JQ-9 m
I eV
= 8.64 x 10- 19 1 - 1.29 x 10-• 9 1 = 7.35 x 10- 19 1
=
Tfu1 s6 nguong:
7.35 X l◊- 19 J
= I. 11 X 10 1 s Hz
o - h - 6.626 >.. 10- l<I J ·
II
<J,
- - - -----,---
16
J)
Bai S - Hi�u ll'ng quang di�n
*D(>ng nang c6 th� duqc kf hi�u la Ek ho�c KE (kinetic energy):
1) Du&i day la cac dfi' ki�n th\l'c nghi�m yg hi�u ung quang di�n cu.a kim lo�i sodium
bu&c s6ng i, rnn
312.5
365.0
404.7
546.l
Dong nang C\l'C dl;li ci'.rn guang 3.41
di�n tu Ek,10- 19J
2.56
1.95
0.75
0\mg d6 thi dong nang - tfui s6 va qua d6 xac d:inh h�ng s6 Planck (h), cong thoat (W) va tful s6
nguong ( v0 ) cu.a kim lo�.
2)
Du&i day la mot s6 dfi' ki�n vg dong nang ci1a electron thoat ra du&i d�.mg ham s6 ct\a btr&c
s6ng cirn anh sang t&i t rong th( nghi�m v� hi�u ung quang di�n cfia sodium:
.Vnm
100
200
300
400
500
KE/eV
I 0.1
3.94
I 88
0.842
0.222
Xay d\mg d6 thi tu cac du ki�n nay thanh m9t dm'mg th�ng, tfnh h�g s6 Planck tu do d6c (g6c
nghieng) cu.a dm'rng th�g va cong thoat �-
17
HU'(mgd�n
1) Chuygn bu&c s6ng ci1a m6i anh sang chi�u x� thanh din s6. DQng nang c\}'c d�i Ek h.rO'ng 1'.mg
v&i t§.n s6 ctta m6i quang di�n tir duqc cho & ban
. g sau:
A.,JUn
312.5
365.0
404.7
546.1
V' 10 14S-1
9.59
8.21
7.41
5.49
Ek , 10-19J
3.41
2.56
1.95
0.75
Tu dfr Li�u t:rong bang, xay d\mg duqc d6 thi E k - v :
4
�--,
3
'o
w 2
1
0
4
5
6
7
8
9
.1
v/10 9
14
10
hv= hv0 + Ek
Suy ra:
£k
h = � = b,.
b,_ V
V- v0
H�ng s6 Planck b�ng do d6c cua. d6 thi Ek - v . Chon 2 digm pht1 hqp tren d6 thi, r6i thay cac gia
tri. Ek va v vao bi8u thl'.rc tren, ta c6:
9
(2.70-l.05)xl0-' J
.
h=
6.60x1034 l•s
14
1 =
(8.50-600 ) xlO s-
Giao digm cua d6 thi v&i hoanh dQ la t§n s6 ngmmg cua kim lo�i:
v0 = 4.36x 1014 s- 1
Cong thoat Ctla kim lol;li la
W = hv0 = 6.60x10- 34 J •SX 4.36x10 14 s- I
= 2.88x10- 19 J
18
2) Tuong n,r bai 1. D6 thi:
20
---.
°' I S
-
......
10
s
0
0 5
5
2
V
110
15
2.S
H.t
3
3 5
<I>= 3.59· 10-' 9 J
19
Bai 6 - Nang ltrQ'llg ion boa
Qua tr1nh ion h6a mc;H nguyen tu hydrogen & tr:;mg thai CO' ban dn 2.l 79xJo- 18 J nang lm,rng. B�
m�t m�t trcri c6 nhi�t do khoang 6000 K va dm;rc t�o thanh, mot ph§.n, la b&i hydrogen nguyen tir.
Hydrogen t6n t:;ti & d:;tng H(g) hay I·i+ (g)?
Hmrngd�n
Nang luqng sfu1 c6 tren b� m�t m�t tr6'i:
2.90 x 10-' m·K
= 4.833 x 10_1 m
6000 K
he
E = - = 4. 1 1 x 10- 19 J
)..
Gi a t:ri nay th�p h011 nang lm;mg din d� ion h6a mot nguyen tir hydrogen, do d6 hydrogen clu\
y�u t6n t� & dl;lng H(g) tren mM tr6'i.
20
Bai 7 - Cong tltwc de Broglie
Anh sang, tnr&c day v6n dm;rc xem la c6 tfnh ch§t s6ng thufu1 tuy, da dm;rc phat hi�n la c6 nhtrng
di;tc tnmg C\l th� ciia h:;it. V�y di�u nguqc l:;ii c6 dl'.mg kh6ng? N ghfa la, ca.c vt chfi.t tlnr<'Yng duqc
xem la hc;1t c6 th� hi�n tfnh chfi.t s6ng khong? Cau hoi nay nay sinh vao d§.u th�p nien 1920 b&i
nha V�t Ii tre ngu<'Yi Phap Louis de Broglie, ngu<'Yi da d�n ra phmmg tdnh sau v@ m6i lien h� giua
bu&c s6ng cua mQt hc;1t v&i dQng lm;rng p (bi�t p = mv): 11,= � = � (plm011g tiinh de Broglie.)
p mv
1) Tinh bu&c s6ng de Broglie trong m6i tnr<'Yng hc;rp sau:
a. Mot electron di chuy�n v&i t6c dQ b�ng 10 % t6c do anh sang.
b. MQt qua bong tennis (55 gram) di chuy�n v&i t6c dQ 80 d�gia (hay 35 mis.)
2) NhiBu xc;1 neub-on duqc d11ng d� xac dinh c§.u true cu.a cac phan tir. Kh6i lu<;Yng m6i neutron
b�ng 1.675·10-27 kg.
a. Tinh bu&c s6ng de Broglie ciia mQt neutron di chuy8n v&i t6c dQ b�g 1.00 % t6c dQ anh
sang.
b. Tfu.b t6c dQ dia neutron v&i bu&c song 75 pm (1 pm= 10- 12 m.)
3) MQt nguyen tir (atom) cu.a nguyen t6 clma bi�t di chuy�n v&i t6c dQ b�ng 1 % t6c dQ anh
sang. Bu&c s6ng de Broglie do duqc la 3.31·10-3 m. Xac dinh nguyen t6.
21
HU'(mgdiin
1) a. 10 % t6c d9 futl1 sang= 0.10 · 3.00 · 10 8 m/s = 3.0 · 10 7 mis.
6.63 X 10 1 Jc;
�. A =
mv
9.11 x 10-' 1 kg x 3.0 x 10 7 mis
1
2.4 x IO 11 m
2.4 x 10 : nm
b.
1
6.63 x l O 1 J
>.. = � =
mv
0.055 kg x 35 mh.
3.4x 10 1· I Ill
3.4-x 10 ·�� nm
Con s6 nay qua nho d�n ml'.rc n6 gfui nlm khong coy nghia. Chl'.mg ta khong th� xac di1tl1 bu&c
s6ng qua nho nay. Y nghla ciia con s6 nay la chung ta chfulg cfui lo l�ng v� t(nh cMit s6ng ciia
die vftt th� d11 l&n.
2)
6.626 x Io-,' J ·
1 675 x 10 r kg x (0.0100 x 2.99 x 108 m/)
u.
A= h =
b.
6.626 x IO � J \
A=� v = � =
mv'
>.m
75 x 10 12 m x J.675 x 10 !" kg
mv
1.32 x IO 13 m
5.3 x I 01 mis
3)
m
6.626 x 10-H kg m 2 le;
h
-- = 6.68 X 10- 26 kg/atom
= --------- ----11
1..
3.31 x 10 ,� m x (0.0100 x 2.998 x 10 m/�)
6.68 x I0-26 kg
6.022 x 10 23 atom!,
1000 g
------ x ------- x -- = 40.2 g/mol
nml
kg
atom
Nguyen t6 do la calcium (Ca.)
22
Bai 8 - Cong tltwc de Broglie
1) Tinh t§.n s6 ciia buck s6ng de Broglie v&i die vi h�t sau:
a. Neutron c6 d911g nang 0.1 eV.
b. Electron t\t do voi. d911g nang 300 eV.
2) Tinh (a) bu&c s6ng va d{mg nang cua m9t electron 1rong cln).m electron dtrQ'c gia t6c b&i hi�u
d.i�n th� 100 V va b) d9ng nang cirn m9t electron c6 bu&c s6ng de Broglie 2 00pm.
3) Anh nhi�u x� d1a m<St hop chtlt dtrQ'C ch\1p b�ng kfnh hi�n vi d.i�n tit truy�n qua voi. d.i�n ap
gia t6c 200 kV. Tinh bu&c s6ng c1ia cln).m d.i�n tu gia t6c.
4) Dong electron chuy�n doi qua hi�u d.i�n thS U c6 d9 dai s6ng la 6.1 pm. Tfnh U.
5) M<St trong nhi1'.ng 1d th u�t hi�n d:;ti hi�u qua nhtlt d� nghien CltU d.u true la nhi�u x� neutron.
Ki thu�t nay lien quan d�n vi� t�.o thanh m9t chum neutron chu§n tnrc 6' m9t nhi�t d9 q1 th�
tu ngu6n neutron nang lu011g cao va dtrQ'C tlwc hi�n 6' m9t s6 nha may gia t6c tren khftp th�
gi&i. NSu t.6c d9 cua neutron dtrQ'C cho b&i cong thuc 'Un = (3ksT/m)112 , trong d6: m la kh6i
ltrQ'Og neutron (l.67· 10-27 kg); ks = l.381 · 10- 23 J K- 1 la h�ng s6 Bontzmann (b�ng h�ng s6 khf
R chia cho s6 Avogadro). Tfnh nhi�t d9 T dn d� cac neutron c6 bu&c s6ng de Broglie b�J1g
50pm.
23
HU'(mgdiin
1) Ta c6:
Dong lm;mg: p = mv
Dong nang: EK= mv2/2
� A= h =-=-===a
h
h
⇒ p= .J2mEK. V'<),y:
.
p
).. =
mv
✓2mEK
6.626x 10 1� J ·.
✓2xl675xl0:-kgx0.k xl 602xl0 J-(cV)
10
1
-11 m
= 9.403x10
b.
A. =
6.626x 10-.l-l J •
✓2x9.109xl0 "kgxl.(>02xl0
19
=7.0 xl0 11111
x�OOV
2) a. Bi�n tich electron· Bi�n th�= 89ng nang/elecu:on
(1.602· 10- 19 C) (100 V) = 1.602· 10- 17 J/electron.
V
=
tn
=
2(1.602 X JO-I? J)
9 109 x IO-ll kg
= 5.93
6
-1
X J Q ffi · S
6.626 X 10-.l-l J S
I 23 x 10_ 10 m
6 m•s- 1) _
11 kg) (5.93
- •
9
l0
09
101
.
x
x
(
A mu
_ !:_ _
b.
11
KE
x 10-" J•s
3_64 x 10 m•
= _hm>._ = (9. 109 6.626
10- kg)(200 10- m) =
X
X
6
12
1
. 09x 10•ll kg)(3.4{,x 106 m-s 1 )
( 91
= 6.02 X 10_,. 1
= 2 =
2
2
mv2
3)
A=
11
6.626xl0 uJ.
J2x9.109xl0 Hkgxl.602xl0 10 rx2xl0 1 V
=2.742x 10-••,,,
24
4) Do dai song la bu&c s6ng A, dong luqng ciia electron se lap = h!A-
(1 )
T6c do cu.a electron la v, dong lm;mg cu.a electron la p = mv
(2)
Dong nang ci1a electron la T = mv 2/2 = Ueo
(3)
T1'r cac bi8u thuc (1), (2), (3) tren ta c6:
5)
A
h
h
- ---�
- m vn - (3mko T) 1/2
Jt.l
T- __....,.2
- 3mk8 l
= 3 (1.67 X IQ 27 kg) {1.381 x 10- 2' J-K- 1} (50 X 10- 12 m) 2
2500K
=
25
Bai 9 - :B«}ng nang va d«}ng htQ'llg
Dong nang ciia phan ur lien h� v&:i nhi�t do T b&i he thirc: E:::
3
k8 T
2
0 day kB = l .387· 10-23 J.K-1 la hfu1g s6 Boltzmann; T la nhi�t do K.
a) Hay tinh dong nang ci1a nguyen tir calcium thoat ra khoi lo & nhi�t do 600°C va tfr d6 tinh
dong lm;mg (p = mv) theo d011 vi. kg.m.s- 1; va v� t6c (theo m.s- 1) c1\a mot nguyen tit calcium
(��Ca) c6 nguyen tir kh6i la 39.96.
b) Cac nguyen tir calcium bi cu6n vao mot cai b§y, & d6 cln'.mg bi quang ion h6a do bi bful pha
b&i ti.a laze c6 bu&c s6ng ";..,::: 396,96 nm. Hay tinh tfut s6 v (theo Hz), nang hrqng (theo .T),
dong lm;mg p (theo kg.m.s- 1) cua mot photon (ti.a laze) c6 bu&c s6ng tren.
c) Tinh momen dong luqng obitan (M = h,jL(l+l), trong d6 l la s6 hrqng ur ph\l) va moment
dong luqng spin ( M .• = h,js(s + 1) v&i s6 luQ'ng ti'r spi n ms= ±s) cua electron trong ion Ca+ &
tr:;ing thai ca ban. Cho bi�t h = : la h�ng s6 Planck rut gon.
2
d) Khi h§p th\1 bite x:;i v&i bu&c s6ng 396,96 nm th1 nguyen tir calcium chuy�n len tr:;ing thai
kfch thich 1mg v&i mire nang hrqng cao tbl'.r nhilt, con h§p th\l bite x:;i v&i bu&c song 393,48
nm thl nguyen tir chuy�n len mt'rc nang lrrQ'Ilg cao tbir hai. Hay tinh bu&c s6ng cua photon
phat ra khi nguyen tir calcium chuy8n n'r ml'.rc nang ltrQ'llg cao tht'r hai v� mt'rc nang hrQ'Ilg cao
tht'r nhilt.
26
HU'(mgd�n
i
a) E::: 1.3807 X10-23 (JIC') X ( 600 + 273) ( K)::: 1.81X10-20 J
2
,
mv2 (mvf p2
7
E=
= -- = - ⇒ P = ,J2mE = .J2x39.96xl.6605x10-2 xl.8lx10-20 = 4.90xl0-23 kg.m.s-'
2m
2m
2
p
V= - = 738(,n/ S)
m
14 1
b) v::: �::: 7.557 x10 (s- )
A,
h
. -27 (kg .m Is)
P::: - ::: l.6692x10
A,
E::: hv ::: 5, 0.10- 19 J
b) Ca + : [ Ar]4s 1, electron d(jc than 4s I c6 l ::: 0, m� ::: ½ v�y s ::: ½ .
c) Mire nanglmmg cao thl'.r nh�ttinh duqc la 5.0x 10- 19 J (xem m1,1c 2.b tren)
Mire nangluqng cao thl'.r hai:
E =he= 5.052xJ0-'9 J
A.
M = (5.052- 5.0)x10- 19 J = 5.2x10-21 = he ⇒ A.= 38226.923(nm)
A.
27
Bai 10 - Cong thwc Rydberg cho nguyen ti'r hydrogen
Cong thl'.rc Rydberg duqc dung trong v�t If nguyen tu d� mo ta cac bu&c s6ng cua die v�ch ph6
trong cac nguyen t6 h6a hc;>c. Cong thl'.rc nay duqc nha V�.t If Th1,1y Di�n Johannes Rydberg cong
b6 vao ngay 5/11/1888.
_
1
1 -I J cm-I (n > n )
v = - = R(2
1
n: n�
'A
Trong do'),., la bu&c s6ng ci1a bl'.rc x� di�n tu (trong chan khong); R;:::: 109680 la hfulg s6 Rydberg;
n, va n2 la cac s6 nguyen hrong 1'.rng v&i cac s6 luqng tir chfnh ciia cac orbital bi chiBm tnr&c va
sau "bu&c nhay luQ'ng tu".
E
e
...
-..,
'
'
l◄---►I
l.ynun
E
E
E
,Q
ci
,0
c,r;
r:
.,.
....
•
•
◄
--------------►
�
... -
or
,0
◄ ►I
►
Balmer
I hr.a, 111le1
E
"' '°
C
C
P.a•lhtn
►
Vt\1hlC'
i
lnlrucd
enc, nnmc
JI I
,,
�- ..
3. � ;
i. s 6, ..
:?. l
L)lllJII
B.1lmc:r
:?
Pa,chc:n
8racl..e1
J
5. <, 7 • •.•
lVIQt gian d6 bi�u dian cac day khac nhau trong ph6 nguyen ti'r hydrogen.
(Day Lyman nfun a vung tir ngo� [ultraviolet]; day Balmer & vung kha ki�n [visible]; con day
Paschen va Bracket & vung h6ng ngo� [infrare d].)
1) S1t d1,mg cong th1rc Rydberg, hay tfnh bu&c s6ng 3 v�ch dfiu tien cua day Lyman.
2) Mot V<,tCh trong day Lyman Clla nguyen tir hydrogen co bu&c song 1.03· 10"7 m. Tim ml.'.rc
nang luQ'Ilg ban dfiu c11a electron.
r
3) Mot nguyen tir hydrogen & t <;tng thai co ban h§p thµ mot photon co bu&c s6ng 97.2 run. Sau
d6 116 phat ra mot photon c6 bu&c song 486 mn. Xac dinh tr�g thai [rnl'.rc nang lm;rng] cu6i
cua nguyen tu hydrogen.
28
HU'(mgdiin
1) Cong thirc Rydberg:
ii=�=
109 680 (� - �) cm- 1
).
nI
(n 2 > 111)
112
V&i v:;i.ch d§.u tien, th� 11 I = I va n2 = 2 vao:
v2 = 109 680 ( /2 - �1) cm 1 = 82 260 cm-•
1
>-1 = � = 121.566 nm
"1
Tuong 1:1,r v&i cac v:;i.ch thtr 2 va 3 la: 102.571 nm va 97.2526 nm.
2) Trong day Lyman, n, = I:
I
- = I 09 680
>..
(
I ) cm-
I -2
/
1
11
I
109 680 cm-• _ _
+ 109 680 cm-•
2
1.03 X I o-l cm
n
n 1 = 2.98 � 3
3) Tr�g thai nguyen hr hych-ogen d�t duqc khi h§p th1,1 la:
(
I
I - = 109680 I - - ) cm-1
----,,97.2 x 10- 1 cm
"/
"1
=4
Xa.c dinh tJ·�g thai cu6i:
I
(..!.. - .2...) cm
= 109 680 42
97.2 x 10- cm
1
n1 = 2
1
n/
29
Bai 11 - S6 song
Bu&c song cirn 4 v�ch Ii�n nhau trong ph5 k.ha ki�n cu.a nguyen tu hydrogen I§n lm;rt Ia: 656.47,
486.27, 434.17 va 410.29 nm. S6 s6ng cua m6i v�ch dm;rc chuy�n d5i toan hoc thanh bi�u thirc
_ (1 lJ , . :. :, , , :,
�
sau: v = R 2-2 . Xac dinh hang so R va cac so nguyen 111, n2.
Il l
112
Hlf<mgd�n
Chuy8n bu&c s6ng thanh s6 song:
Ai= 656.47nm
v1 = 15233cm- 1
/4i = 486.27 nm
v2 = 20565cm- 1
� = 434.17nm
v3 = 23032cm- 1
A4
= 410.29nm
V4
= 24373cm- 1
Do cac v�ch li�n nhau, c6 th� d�t n 1 = m, 112 = m+ 1, m+2, thu duQ'c cac bi�u tht'.rc sau:
15233 = ..!!.__
R
m2 (m+1) 2
R
20565 = ..!!_2 _
m ( m+2)2
R
23032 = ..!!._2 _
m (m+3) 2
R
24373 = ..!!.__
2
m (m+4) 2
Liy bi�u tbirc thu nh�t cbia cho bi�u thirc tbu hai:
2
15233 (2m+l)(m+2)
= 0.740725
=
3
20565
4(m+l)
Thu dm;rc m = 2. Dua m vao bit k1 cong thirc nao trong s6 4 c6ng thl'.rc tren, thu duQ"c:
30
Bai 12 - Ph6 hydrogen
Trong m9t thf nghi�rn, ngmn ta ghi duqc ph6 phat Xl;l (ph6 V?.ch) d6i v&i m9t ion gi6ng hydrogen
(chi chua m9t electron) & phase khf. Cac Vl;lch ph6 ci1a ion kha.o sat dtrQ'c bi�u di�n theo h1nh ph6
d6 du&i day:
A
B
--Wavclc:npth-
Tfit ca cac v:;ich ph6 tlm duqc d�u d�c tnmg cho cac bu&c chuy�n tfr trl;lng thai kich thfch v� tr:;i.ng
thai ung voi n = 3. Can CU' vao cac dfr ki�n da cho, hay:
a) Cho bi�t bu&c chuy�n electron nao 1'.mg v&i v:;ich A va v:;ich B gbi tren pb6 d6?
b) Gia sfr dQ dai bu&c s6ng (wavelength) A= 142,5 nm ung v&i v:;ich B. Tinh dQ dai bu&c s6ng
cho v�ch A theo nm.
Htrong diin
a) Vi bu&c s6ng ti I� nghich v&i nang luqng, E = he/A nen v�ch quang ph6 & ben phai ciia B (&
bu&c s6ng 16n hon) 1:trO'ng 1'.mg s1,r chuy�n doi v� muc nang luqng thfip nh�t c6 th�, nghfa la 1:t'r n
= 4 xu6ng n = 3. V?ch B 1:trO'llg rrng s1,.r chuy�n doi v� muc nang luqng th�p nhfit k� ti�p tun= 5
xu6ng n = 3 va Vl;lch A tuong 1'.mg v&i s1,r chuy�n d&i electron tun= 6 xu6ng n = 3.
d) Vi ph6 nay la danh cho ion m(>t electron nen ta ap d1,rng cong thuc.
E=-13.6 : (eV)=-13.6·1.602·10-I9 x : (l)=-2.719·10-ll!_z: (J)
nnn2
2
(])
Sfr d1,mg v:;ich ph6 B d� xac dinh Z
(2)
D.E
5 3
➔
=he= 6.626·10 -34 (J.s)·3.0·108 (m/ s) = 1.
;i,
142.5·10-9 m
395_10_,� J
Nang luQ'[lg toa ra la : -1.395· 10- 18 J
Tt'r (2) va (3) ta c6: -2.719·10 - 18-
vay d6 la ion Li2+ v&i Z = 3.
162 2 = l.
395 ·10- 18 ⇒ Z = 3
9·25
31
(3)
8
18
2
AD
--27
_ _!_ (J
. 1 9.10 - x3 (_!_
6➔J =
32 52 ) )::::-l.634·10-' 1
he :::: 6.626·10-34 (1.s)x3.0-108 (ml s)
:::: 1.216·10-7 ,n:::: 121.6nm
1-1.634-10-,s1c1)
A 1�EI
::::
32
Bai 13 - Ph6 cua hydrogen
a) T§n s6 cu.a cac v�ch ph6 thu9c day Lyman (bu&c chuy�n electron tir n >1 v� n=l) c11.a
nguyen tir hydro 15n hrqt la 2.466; 2.923; 3.083; 3.157; 3.197; 3.221; va 3.237 x I 0 15 Hz. D\ra
vao cac gja tri nay hay xac dinh nang lm;mg ion h6a cu.a nguyen tir hydrogen.
b) Ti.uh nang luQ'llg ion h6a thir nh§t (kJ/mol) cu.a cac nguyen tir selenjum, bi�t khj chj�u chum
sang don s�c c6 bu&c song 48.2 nm vao cac nguyen tir selenium & tr�ng thai C(J ban va & th�
khf thl t�o ra chum electron c6 v:;in t6c 2.371 x 106 m/s. Bi8t kh6i hrQ'tlg cfia I electron b�ng
9.109x 10-31 kg.
Hmrngd�n
a) Nang luQ'ng ion h6a img v&i nang luc;rng cu.a bu&c chuy�n n = oo v� n = 1 (cung gia tri nlumg
h
khac diiu). Dl,l'a vao cong thirc Bohr c6 th� thiiy khi gia tri n cang l&n tl cac mire nang luqng
cang gfui nhau, s\r khac bi�t tfui s6 cfia birc x� se cang nho. L�p bang gia tq chenh l�cb tful s6
theo du ki�n d� bai ta c6:
2.466 2.923 3.083 3.157 3.197 3.221 3.237
T�n s6 x 10 15 Hz
Chenh l�ch tiin s6 X 10 15 Hz
0.457 0.160 0.074 0.040
Ve d6 thi chenh l�ch illn s6 theo t�n s6, ta c6 d6 thi
N
�.
0. .5
04
03
(l I -
(t -+----..-----.----......-----._,_____,,
2 50
2.75
J.25
3.00
33
3.50
0.024
0.016
Ngo�i suy d6 thi dt t:11,lC t§.n s6 �i t§n s6 3.275 X I 0 15 Hz. Vi,iy gia tii nang ltrQ'ng ion h6a = Eoo =
(6.62x 10-34 J/s) x (3.275x 10 15 l/s) x (6.02x 1023 l/mol) = 1307 kJ/mol.
b) GQi I I la nang luQ'ng ion h6a thl'.r nh§.t cfla Se (J/nguyen tir)
ltC
=/ 1 +-21 nw 2
1.
⇒ 6,62, 6Xl0-34X3,00Xl0 =
8
48.2X10-9
Jl
+� X 9.109 X lQ-31(2.371 X 106)2
2
34
Bai 14 - Ph6 cua nguyen ti'r hydrogen
V6'i nguyen tu hydrogen:
a) Tinh bu6'c s6ng cu.a cac v�ch ph6 t�o thanh b&i S\l chuy�n tfr tn;mg thai kfch thfch thu 1 va
tn,mg thai kfch thfch thl'.r 6 v8 tr�ng thai cCJ ban d� giai thfch day v�ch chua chung va vung
ph6 chung thuC:k v8.
b) Cac photon duqc t�.o ra b&i hai v�ch tren c6 th� gay ra (i) s,r ion h6a nguyen tu hydrogen
khac 6' tr�ng thai co bin hay khong? (ii) s,r ion h6a cac nguyen tu d6ng trong kim lo:;ti d6ng
hay khong (cho bigt cong thoat cau d6ng la 7.44-10- 19 J)?
c) Ngu each photon tl'r hai v�ch ph6 tren c6 th� kfch thfch cac electron trong tinh thS kim lo�i
d6ng, hay tinh bu6'c s6ng cu.a quang di�n tir (photoelectron) buc x� tt'r b8 m{lt tinh th� kim
lo:;ti d6ng.
35
HU'(mgdiin
a) Nang hrc,rng & cac tr�ng thai ciia nguyen tfr hydrogen duc,rc tfnh theo:
1
E,, = -2. J 8 X JO-is • 2
n J
Trong d6 n la s6 luo-ng ttt chfnh.
Chenh l�ch nang lm,rng gitra tn,mg thai kich thlch d�u tien (n = 2) v&i tn;mg thai ca ban (n = 1) la:
4
.6.E1 = E2 - E1 = (-2.18x10- 18 • � J)-(-2.18x10- 18 • J) = 1.64x10- 18 J
2
1
Bu&c song Clla ph6 bl'.rc Xl;l b&i nguyen ttt tl'r tfl;lng thai kich tluch thl'.r nh�t vs tr:;ing thai co· ban la:
8
1
3'1
A = ch (2.9979 x10 m· s- ) x(6.626x10- J · s) 121nm
1
=
l.64x10- 18 J
.6.E1 =
Chenh l�ch nang hrQ'llg gifut trc;lllg thai kich tmch thl'.r 6 (n = 2) v&i trl;lllg thai ca ban (n = 1) la:
.6.E6 = E7 - El = (-2.18x10- 18• �J) -(-2.18x10- 18 --;-1) = 2.14x10- 18 J
7
1
Bu&c song cita pb6 bl'.rc x;;i b&i nguyen ttt u'r tr1;1ng thai kfch thicb thl'.r 6 v� tr:;ing thai ca ban la:
1
8
34
A6 = ch=(2.9979xl0 m·s- )x(6.626xl0- J·s) =92_9nm
2.14x10- 1 8J
M6
Ca hai v:;i.ch d�u thm)c day Lyman va nfun trong vung tir ngo:;i.i.
b) Nang hrqng t6i thi�u d� ion h6a nguyen tir hydrogen & trl;lllg thai ca ban la:
.6.Eco=Eco-E1 =-EI =2.18X 10- 1 81
va .6.E1=1.64x10- 1 8J<.6.Eco
.6.E6=2.) 4X10- 18J<.6.Eco
V�.y cac photon sinh ra b&i hai Vl;lch ph6 tren khong th� ion h6a cac nguyen tir hydrogen & t::r:;ing
thai ca ba.n. Tuy nhien :
.6.E 1 ><D eu =7.44X) o-19J
.6.E6><Dcu =7.44Xl 0- 19J
V�y cac photon nay c6 th� ion hoa cac nguyen tir trong tinh th� kim lo:;i.i d6ng.
c) Bu&c s6ng ct\a cac quang electron buc x� tu tinh th� d6ng la:
.l=�=}:__=
p
mv
h
✓2m.6.E
36
Trong c6ng thuc, .6.E la chen.h l�ch nang lttQ'ng ciia photon chi�u xt,l tren tinh th� va c6ng thoat
cua c16ng (<DCu). D\ra va.o c6ng thuc tren, tinh dttQ'c bu&c song quang di�n tfr buc x� boi tinh th�
c16ng sau khi chi�u x� photo ung voi hai v�ch ph6 nguyen ti'r la.:
A,'=
/4� =
6.626x10-34] ·S
[ (2x9.1095 X 10- l kg) X (I .64x] o-lS J - 7.44x103
l
19 ]
)
]2
6. 626 X} (f34 ] • S
[ (2x9.1095x10- kg) x (2.14x10- J - 7.44x 1031
18
37
19 ]
)
I
]2
= 519pm
= 4}5pm
Cau hinh electron
Bai 15 - Cac s6 hrc;mg tu
1) Nhung bQ s6 lu<rng tu nao sau day khong thoa man? V&i cac bo s6 hrqng nt khong chfnh xac,
hay sua l�i cho dimg.
a) n = 3, I = 3,m1 = 2.
b) n = 4, I = 3,m1 = 4.
c) n = 0, l = 0,m1 = 0.
d) n = 2,1 = -1,m, = l.
2) Nhung bQ s6 luqng tu nao sau day khong thoa man? V&i cac bo s6 luqng n'.r khong chinh xac,
hay sua I� cho dimg.
a) n = 3, l = 3,m, = 0,ms = -1/2
b) n = 4, I = 3,m, = 2,ms = -1/2
c) n = 4, 1 = 1, rn, = 1,ms= + 1/2
d) n = 2, l = 1,m1 = -1,ms= -1
e) n = 5,1 = -4,m1 = 2,ms= +l/2
f) n = 3,l = 1,m1 = 2,ms = -1/2
3) Sip x8p cac electron c6 s6 luqng tun, 1, m, s hrong rrng v&i nhfmg trm'mg h01J sau theo thfr
ti,r nang luqng giam d§n:
A (2, 1, 1, +1/2)
B (1,0, 0, -1/2)
C (4, 1, -1, + 1/2)
D (4, 2, -1, + 1/2)
E (3, 2, -1, +1/2)
F (4, 0, 0, +1/2)
G (2, 1, -1, +1/2)
H (3, 1, 0, + 1/2)
38
HU'(mgdiin
1) a) Cac b() s6 luQ'Tlg tit nay hQ'p Ii; b) V&i I = 3, m1 c6 th� c6 gia tri. tl'r -3 d�n +3, do d6 +4
khong thS duQ'c ch�p nh�n; c) n khong th� b�ng O; d) I khong th� la s6 am.
2) a) V&i n = 3, I= 3 khong th�; b) hqp If; c) hqp lf; d) ms khong thS b�ng-1; e) I khong thS la s6
am; V&i I= 1, m1 khong thS b�ng 2.
3) Electron c6 nang htQ'Tlg th§p nh�t khi electron c6 gia t1i. n nho nh�t; n�u cac electron c6 dmg
gia tti. n th1 electron nao c6 t6ng n+I nho hon thi c6 nang htQ'ng th§p hon. V�y nang htQ'ng d'ia
cac elecb·on tang dfin theo thl'.t t,r: B < A = G < H < E < F < C < D
39
Bai 16 - Nguyen tfr nhi�u electron
Tinh s6 electron cl,l'c d�i trong ng uyen nr th6a man die b9 s6 luQ'ng tu sau:
a. II = 4
h. 11 = 5, ,,,, = + I
C.
11
= 5, 111 = +1
1
d. II= 3, f = 2
e. II= l. ( = I
f. II = 0, ( = 0, Int = 0
I
g. 11 = 2, ( = l,m, = -l,m - -2
h. 11 = 3, m, = +l
I. 11=2 l =2
I· II= I, f = 0, m, = 0
Hm'mgdfin
h
a) n = 4 t'i l c6 th� la 0, 1, 2, 3. Do d6se c6 ca.c orbitals (2e), p (6e), d (lOe), f (14e), do d6 t6ng
s6 electron d� l�p d�y cac orbital n ay la 32.
b) n = 5, I = + 1: v&i n = 5 tb'i I = 0, 1, 2, 3, 4; v6i 1 = 1, 2, 3, 4 thi d8u c6 m1 = +l, do d6 c6 4
orbital 1ieng bi�t, hrm1g img v&i 8 electron.
c) n = 5, ms = + 1/2: v&i n = 5, I = 0, 1, 2, 3, 4. S6 orbital v&i m6i gia tri l l�n hrQ't la 1, 3, 5, 7, 9.
Do d6 c6 t6ng cong 25 orbital v&i n = 5, chung c6 th� chl'.ra 50 electron va 25 trong s6 d6 c6 m s =
+1/2.
Cacy ti�p theo 1€tp lu€tn tuong n,r.
d) 10 electron.
e) 6 electron.
f) 0 electron.
g) 1 electron.
h) 9 electron.
i) 0 electron.
j) 2 electron.
40
Bai 17 - Nguyen tfr nh i�u electron
Vi�t c�u hlnh electron tr�ng thai co ban cu.a:
I) Nguyen t6 co 1 electron 5p clnra ghep c�p, c6 th� t<10 thanh hQ'p chit c9ng h6a tri v&i
fluorine.
2) Khf hi�m v&i die electron chi�m orbital 4f.
3) Nguyen t6 ki�m th6 sau radium (clnra dm;rc phat hi�n).
4) Kim lo�i chuy�n ti�p elm ki d§u tien nhi�u electron chua ghep c�p nhit.
HU'(rngd�n
a) Ca In va I d�u co 1 electron 5p chua ghep c�p nlnmg chi c6 phi kim I m&i c6 thS t�o thanh
h<;rp ch�t c9ng h6a tti v&i fluorine.
I: I KrJS 14d 10 5p�
Sp
1
b) Rn: [Xe]6s24f 145d 106p6 .
c) Nguyen t6 dose c6 Z = 120. [Rn]7s2 5f 1 46d 107p68s 2 .
d) Do la clu-omiwn, mQt ngo�i le v� tr�t tl,f di�n electron. Cr co 6 electron chua ghep c�p (ti�p
theo la Mn v&i 5 electron).
41
Bai 18 - Cfiu hinh electron
Hay giai thfch v1 sao:
a) Trong cac hqp ch�t magnesium t6n t?i & d�g Mg2+ nlnmg kh6ng t6n t?i & d�g Mg+ , m�c du
d6i v&i nguyen tu Mg, nru1g ltrqng ion hoa thu hai (15.035 eV) l&n gftn gftp d6i nang hrqng
ion boa thl'.r nhit (7.646 eV)?
b) Ti (Z = 22) t:;to dnqc cac ion c6 di�n tich khac nhau: +2, +3, +4, b:ong d6 ion Ti(II) va Ti(III)
d�u c6 mau, con Ti(IV) khong?
Hll'01tg d�n
a) Ion Mg 2+ c6 kich tlm&c nho h011 nlnmg 1� c6 di�n tich cao hon ion Mg+, do d6 nang hrqng
m:;tng ltr&i phat sinh khi h1nh thanh cac hQP chftt cua cac ion Mg 2+ 16'n h011 nhi�u so v&i nang
ltrQ'llg phat sinh n�u cac ion Mg+ hinh thanh hc:rp chit. Chfnh S\t tang nang lnc:rng m:;ing hr&i bu
tn'r qua nang luQ'ng ion hoa 16'n cua ion Mg2 +. M�t khac, Mg2+ c6 du h1nh b�n cua khf hi�m Ne,
con Mg+ khong c6 du hlnh b�n ciia kb.f hi�m.
b) Ti (s6 tbu t\t 22) c6 du hlllh electron [Ar]3d2 4s2 , do d6 Ti c6 th� hlnh tbanh ion Ti(Il) khi mtt
2 electron 4s, ion Ti(ill) khi mftt them 1 electron & phan 16'p 3d va ion Ti(IV) khi m�t ca 4
electron boa tri. Cac ion Ti(Il) [Ar]3d 2 va Ti(ill) [Ar]3d 1 c6 mau do s\r cbuy�n electron giua cac
ocbital d (da bi tach ra); con ion Ti(IV) khong mau v1 khong con electron hoa tri d nua.
42
Bai 19 - Nang lmyng lien k�t electron
Cho bi�t cac gia tri nang hrqng ion h6a ci1a nguyen tu Li lfu1 lm;tt la l1 = 5.39 eV, Ii= 75.64 eV,
va l3 = 122.45 e V. Tinh nang lu<;Yng lien k�t electron ls cua nguyen ttr Li.
HU'(mgd§n
Theo dinh nghfa nang lu<;Yng electron, c6 th� viM dn<;Yc cac bi�u thtrc sau:
( 1)
(2)
(3)
C6 2 each lam
each 1
Theo dinh nghfa, nang hr<;Yng lien k�t electron ls dia nguyen tu Li la:
va
(3-0.85)
3
_
,
E + ls2.,·
1 ' --13.6eVx-, -13.6eVx
)
(
122
2
/.1
=-138.17eV
(4)
E · I.,2 2s1 =-(J1 +I2 +I3 )=-(5.39+75.64+122.45)eV
)
(
l.1
= -203.48eV
(5)
va do d6
E,s = -[ ( 4)-(5)] = (5)-( 4)
=-203.48eV -(-138.17eV) � -65.3eV
Cach2
43
ELi (1s ) -EL, (1s 2.t ) -E
2+
2
+
1
1
(3- a-)
(3- 0.85 )
'J
= 13.6x -------�-eV = 15.?eV
E= 13.6eVx
24
2
2
Nang luQ'Jlg lien k8t electron ls la:
E, ·' = ELi(1s-2s
, ') - ELt-+(Is, 2s')
= 15.7eV-5.39eV-75.64eV = -65.3eV
44
Bai 20 - Nang lmyng ion h oa
1) a) Vi�t pluro>ng trin.h bi�u di�n qua. t:Linh dtrQ'c quy u&c v&i gia tri IRi cu.a Sn. Day la qua tiin.h
toa hay thu nhi�t? b) Gia tti (IE1 + IE2 + lE3) ci1a Al duQ'c guy u&c cho qua trtnh t6ng nao?
2) 4 gia t1i nang lm;mg ion h6a d§u tien cf1a nguyen tft X la 403, 2633, 3900 va 5080 kJ moi- 1•
D\t doan nguyen t6 X thuQc nh6m nao trong bang tu§.n hoan. Giai thfch.
Hll'61tg d§n
1) a) I& cu.a Sn la nang hrQ'ng ion h6a thl'.r 4. Day la nang luQ'llg d.n d� lo�i electron thl'.r 4 tt'r Sn
& tr�.ng thai khi. Plm011g tiinh tuong ltng v&i qua tr1nh nay la: Sn3+(g)---+ Sn4+ (g) + e
Qua trlnh nay dn nang lm;r.ng, do d6 bi�n thien enthalpy c6 d§.u du01lg (phan l'.rng thu nhi�t).
b) (IE1 + IE2 + 1E3) la t6ng 3 gia tti nang hrq.ng ion h6a d§u tien cuaAl(g) va. tu011g l'.mg v&i bi�n
d6i: Al(g)---+ Al 3+ (g) + 3e. Qua tr1nh nay c6 th� duQ'c diSn giai qua mQt chu tr,nh nhi�t dQng hoc
nlm sau:
1
I (g) __
IF.._� --- At:? (g}
-c
2) Gia ui IE1 << IE2, cho th§y vi�c ta.ch electrnn d§u tien la tu011g dBi dS dang, nlnmg cac
electron ti�p theo thi doi .hoi nhi�u nang lm;mg hem. Xu lmong nay la d�c ti1mg ciia cac nguyen
t6 nh6m 1, do d6 X la kim loc;ti ki�m (th\tc t�, X la rubidium, Rb).
E
:i2
.H)()()
�
ti
C:
0
C:
0
-� 2000
�
C
0
I
0
I
I
I
'
'
0
I
0
1
,
I
,,
d
I
3
,,
J)
I
.t
t,. lcctron rcmm cd
45
Bai 21 - PhlfCmg phap Slater
Tinh 4 gia tri nang luQ'ng ion h6a dia nguyen tir Be b�ng phum1g phap Slater, va xa,c dinh m6i
lien h� gitra k�t qua tinh duqc v&i s6 oxid h6a ph6 bi�n dia Be.
HU'Cmgd�n
Be (g) � Be+ (g) � Be2+ (g) � Be3+ (g) � Be4+(g)
Bi�n d:6i c§.u h1nh electron
(1s) 2 (2s)2 ➔ (1s )2 (2s)' ➔ (1 s 2 ) ➔ (1s 1 ) ➔ ( 1s 0 )
·�-,�-� _________________,,
'-----..--'
11
12
'----,�
l3
'•
Theo dinh nglua v� nang luQ'Ilg ion h6a cua n guyen ur:
Sir d\lng phuO'Ilg phap Slater d� tfnh cac muc nang hrQ'Ilg ion h6a cua Be:
[
,
']
4-0.85x2-0.35 4-0.85x2 /1 =- -I3.595eVx (
)
) x2+I3.595eVx (
2
2
22
=7.87 leV
2
(4-0.85x2)
,
I,- = - [ -I3.595eVx
] = 17.98eV
22
/3 = -[-13.595eVx( 4-0.3) x2+ 13.595eVx16] = 154.8eV
/
4
=-(13.595eVx42 ) = 217.SeV
K�t qua tfnh toan chung minh 1ing:
!4 > /3 > /2 > II
ti-011g d:6 h va 11 g§n nrong OUO'llg (10 e V); l4 va h ding chenh l�h khong qua 1611, nlnmg b va b
thl khac bi�t r§.t nhi�u (136.8 eV). Do d:6, nguyen tir Be d8 m§.t cac electron 2s d:8 tl;IO thanh hqp
ch§.t c6 s6 oxid h6a +2.
46
Bai 22 - PhU'Cmg phap Slater
Sir d1,111g c6ng thuc
*
n2
r =-a
z· o
Tfnh ban kfnh hi�u dl).ng r* dia cac orbital 3s va 2p trong nguyen tir Nava F. Trong d6 n va Z *
la s6 lmmg t:ir chfnh cua orbital va di�n tich h:;it nhan hi�u di.mg tac dong d8n cac electron trong
orbital.
HU'Cmgd�n
Trl;lng thai ca ban ciia Na: (ls)2 (2s)2(2p)6(3s) 1
z· (3s) = 11-1.00x 2-0.85x 8 = 2.2
z* (2p) = 11-0.85x 2-0.35x 7 = 6.85
Th� vao cong thuc:
•
2
2
r (2p) = -a0 = 0.58a0
6.85
Tn;ing thai ca ban ci1a F: ( 1 s) 2 (2s)2 (2p)5
Z.. (3s) = 9-1.00x 2-0.85x 7 = 1.05
z· (2p) = 9-0.85x 2-0.35x 6= 5.2
Th� vao c6ng thuc:
47
Bai 23 - Nang hrQ11g ion boa
Bi�t rfing nang lm;mg ion h6a thfr nh§t cu.a nguyen ttr He la I,= 24.59 eV, tfnh:
a) Nang hrQTig ion h6a thir hai.
b) Nang lttQTig tr�.ng thai ca ban.
c) Nang htQTig tri�t tieu cua 2 elecn·on trong orbital ls.
cl) Cac hfulg s6 ch�n.
e) Nang luQTig trc;1ng thai ca ban cua H· tu k�t qua nh?n duqc & yd.
HU'(Yngd�n
a) Nang luqng ion h6a thit hai (h) ciia nguyen tlt He la nang luqng t6i thi8u c�n cho qua trlnh ion
h6a ti�p theo: He+ (g) ➔He2+(g) +e
He+ c6 th� xem nlm "nguyen ttr" d<JI1 di�n tit, do d6 c6 th8 tinh bfing cong thirc:
)
.
22
l-? =-Elie.. =- -13.595eVx-? =54.38eV
1(
b) Nang luQ'tlg nguyen tt't He & trc;1ng thai C(Y ban:
He(g) ➔He+(g) +e
/1
= £He+ - £He
(l)
He +(g) ➔He2+(g) + e
l· 2 =EHe -EHe
z.i.
+
(2)
Tt'r (I):
Th� vao (2):
=0 - ( /1 +/2 )=-( I, +I2 )
=-(24.59eV +54.38eV)=-78.97eV
M& n}ng ra, mQt nguyen nt da di�n tu A chl'.ta n electron c6 nang luqng & trc;1ng thai co ban bfing
gia tri am cua t6ng nang luqng ioa h6a & m6i giai doc;1n:
48
i=I
c) Dl;it J(s,s) la nang lm;mg tri�t tieu lfu:i nhau cua 2 electron ls trong nguyen tu He:
Elle = 2E11e+
+ J (S,S)
J (S,S) = Elle - 2£11e+
= -78.97eV-2x (-54.38eV)
= 29.79eV
d) Tfnh h�ng s6 chful:
2
(2-(7) ] x
[
x
3
eV
2
.595
E11e = -I
2
I
(7-
2 _[
Elle
(-13.595eV)x2
]
I
2
_
2_[
-78.97eV ]
(-13.595eV)x2
I
2
= 2-1.704� 0.3
e) H- la m{?t ''nguyen tir" lrra:ng di�n tlf (2 electron) vm di�n tfch h:;i,t nban b�ng 1, c6 c!u hi.uh CO'
ban la (1 s)2 va nang lrr()'ng & t:r:;tng thai CO' ban Ia:
Ew =[-13.595eVx(l-(7) ]x2
2
=[-13.595eVx(l- 0.3f]x2
=-13.32eV
49
Bien doi tinh chat trong bang tuan hoan
,
?
,
'
Bai 25 - Bang tufin hoan moi (1)
T§t ca cac nguyen t6 tren Trai dftt d�u duqc x�p vao bang h� th6ng tufu1 hoan d� bi�u di�n tinh
chfti tu�n hoan ciia n6 Tf nh chfit nay c6 th� duqc giai thfch b�11g each sfr d\lng h� th6ng b6n s6
hrqng tir n, I, m,, ms. Vf d\1 v&i n = 2 se c6 t6ng cong 4 orbital g6m 1 orbital 2s (I = 0, m, = 0) va
3 orbital 2p (I= 1, m1= -1, 0, 1). Gi a thi�t r�ng c6 s\r t6n t�i cu.a mot vu h"\l khac tht electron se
duqc s�p x@p theo each khac d� �o thanh mot h� th6ng tuful hoan m&i. Luc nay, b6n s6 luqng tir
11, 1, m1, m� v§n chiu anh lm6'ng cu.a tinh chfit tufu1 hoan nlumg da theo mot quy lu�t hoan toan
khac. ChfuJg h�n, n phai la mot s6 nguyen duong (n > 0), 1 la mot s6 nguyen b�ng ho�c l&n hon 0
nlumg be hon n (0 :S 1 :S n), m, phai la mot s6 le (0 khong phai la s6 le) va c6 th� mang gia tti
duong ho�c am. D6i v&i gia tri m1 duong thi 1 :Sm1 :S 21, con v&i gia tti m, am thl -21 :Sm, :s -1. S6
hrqng tfr ms c6 th� nh?D gia tti 1/2 ho�c -1/2. D\ra vao nhfrng quy lu�t nay, hay:
a) Xay d\ffig tfit ca cac nguyen t6 trong bang tu§n hoan m&i tl'r n = 1 d@n n= 3. V&i n= 1 trn cac
nguye11 t6 duqc ki hi�u lfu1 hrqt la Al, A2, ... v&i n = 2 thi Bl, B2, ... v&i n = 3 thl Cl, C2.
b) Xac dinb c6 bao nhieu nguyen t6 ung v&i 11 = 4.
50
HU'(mgdiin
a) Vcri 11 = J lhi
guycn l6 c6: / - 0, m,- o. m, - ± I /2 khdng tdn l{li do khong c6 m,- 0
guycn l6 c6: ,- 1. m,- ±) • ,,,_ = ±1/2 se tbn t�i 4 nguycn t6
V6i " = 21hi
guycn t6 co: / - 0, m, = 0, m, - ± 1/2 khong t6n l�i
guyca to c6: / I. m, = :ti . m, = ±1/2 sc t6n toi 4 nguycn to
guyen t6 co:/= 2. m, =±3, m, ;: ±1/2 ·e t6n l(li 4 nguyen t6
6i 11 - 3 1hl
guyen t6 co: / = 0. 1111 = 0, m, =±I/2 khong t6n t{li
guycn tO c6: / - I, m, - ± I ' 111, - ± 112 I! t6n t�i 4 nguycn td
guycn t& co:,= 2. m, = ±3. m, = ±112 e t6n 41i 4 nguycn rb
guycn t6 c6: / = 3, m, = ±3;±5 'm, =±I /2 ·c tdn l(li nguycn 16
Viy t6ng CQng c6 16 nguyen 16. Cac nguycn u3 nay c6 the du�c x6p ao bang min
hoan m6i thco ba kiJu
Kieu 1 ·
Al A2
Bl
('I
83 84
82
C!
Cl
C4
Kicu 2·
c1
CS
I ((, I I I I I I
C7
I I I c.i I I I c1 I
a
CJ
cs
Kicu 3:
Al A2 A3 A4
Bl
82
Cl
(.'2
C6
(8
Bl
t
CR
Cl I
C 10
C9
82
CIO
83 B4 85 Il6 B7 88
ta C7 (.'!I c
CJ (.4 (,5
83
C it
Cl!
B5
86
( 13
( 1-1
Al
A2
84
B5
B6
Cl2
CIJ
(.14
B7
B
CIS
('lb
A3
A4
B7
88
CIS
Clb
I uo I u1 I I cu I c1.i I tts I Cit»
u1
b)
guyen lo c6: / = 0. 111, = 0. /Il l= ±1/2 khong t6n t�i
guycn 16 co: I:: I, 1111- ±1 . m, -±1/2 c t6n t(li 4 nguycn t6
guycn t6 co: J- 2. m1 - ±3, m. = ± 112 s� t6n t�i 4 nguyen t6
Nguyen t6 c6: /- 3. m,- ±3;±5 , m, = ±112 e t6n t�i nguyen to
guyen t6 CO: / = 4, 111/ = ±5:± 7 . Ill\ = ± I /2 e tf>n t\li nguyeo t6
Nhu v�y chu ky 4 � c6 24 nguyen t6 15t ca
Voi11 = 4lhi
A3 A4
51
Bai 26 - Bang tu�n hoan moi (2)
MQt liin nQ, d� tieu khi�n, Diing t�o hoa quy�t dinh s�p x�p l�.i mQt trong nhfmg Vii t11,1 ciia Ngai,
khi�n tr& nen phtrc t�p hO'n Vii tr\1 chimg ta dang s6ng. Ngai di�u chlnh l�i orbitan cu.a electron
b�ng each chinh l� spin, lam bi�n d6i m()t s6 plurO'ng t:dnh luqng tfr cu.a chuy�n d()ng electron.
Trong Vfi tn.1- nay, cac s6 luqng tfr cu.a electron tuan theo nhung quy lu�t 1:ttong 1:\r nlnr trong Vfi
L+l
tn,1 ci1a chung ta, ngo�i tn'r m()t di�u: spin ctia electron v&i s6 luqng tir orbital l la: s:::: -- .
2
Nguyen li Pauli thoa man v&i m<;>i spin.
1) Xac dinh gia tri spin cu.a cac electron tren orbi tal s, p, d trong Vfi h·\1 nay. Trong m6i orbital
s, p, d c6 bao nhieu electron?
2) Trong Bang tu�n hoan ci1a Vfi t11,1 nay, & chu kl thir hai c6 bao nhieu nguyen t6?
3) Vi�t c�u blnh electron l&p ngoai cung cfia cac nguyen t6 tuong duong v&i kim lo�i ki�m va
halogen trong Vfi 111,1 chung ta. Xac dinb s6 oxid hoa qrc d�i cu.a cac halogen.
4) Vi�t c�u hlnh electron cu.a nguyen t6 thir sau trong Bang tu�n hoan cu.a Vfi tl.11 nay. 0\ra vao
c§u hinh nay, xac dinh cong thtrc phan tir cu.a hqp ch�t hydrogen (c6 s6 oxide hoa) cao nh§t
Clla nguyen t6 nay.
5) Bllt diiu tt'r nguyen t6 nao thl c�u hlnh electron se khac v&i cac nguyen t6 t6n ti trong Vu 1:l.1,1
Clla chung ta.
6) Phu011g hinh chuy�n d()ng cu.a electron trong Vu 1:l.1,1 cu.a chung ta ten la gi?
52
HU'(mgdiin
1) s-orbital: 1 = 0, s = 1/2, m s = ±1/2. Hai electron co gia tr:i. ms khac nhau co th� d�t vao ct\ng
mot orbital.
p-orbital: 1 = 1, s = 1, m s = 0, ± 1. Ba electron voi gia tr:i. ms k.hac nhau co th� d�t va.o cung mot
orbital.
d-orbital: 1 = 2, s = 3/2, m s = ±1; ±3/2. B611 electron v&i gia tr:i. ms khac nhau co th� dM vao ct\ng
mot orbital.
2) Trong chu k1 thir hai, cac phan l&p 2s va 2p duqc liip dliy. Phan l&p 2s chira 1 orbital, con
phan l&p 2p chira 3 orbital (m6i phan l&p chira 3 electron). T5ng s6 nguyen t6: 1- 2 + 3- 3 = 11.
3) Cac kim lo�i ki�m chira 1 electron tren s-orbital cung nlm trong Vu 111,1 cua chung ta. C�u hlnh
electron la ns 1.
Halogen thi�u 1 elech·on d� lftp d§y p-orbital (c6 3 electron tren m6i orbital). Cftu hlnh electron
la ns2np8 . S6 oxid hoa qrc d� cirn halogen hrong frng v&i vi� lo� ca IO electron - nglua la+ 10.
4) Cftu hlnh electron ciia nguyen t6 tht'r sau gi6ng v&i Vu tn,1 cila chung ta: 1s2 2s2 2p2 . 4 electron
duqc d�t & l&p ngoai cung. C� 7 electron d� hoan thanh l&p nay va cac electron nay c6 th� lfy
t
tu cac nguyen tfr hydrogen - tmmg frng v&i cong thuc EH1.
5) 10 nguyen t6 dliu tien c6 cftu hlnh electron gi6ng Vu tiv cua chung ta. Cftu hlnh electron cirn
nguyen t6 thu 11 la 1s2 2s2 2p7 .
6) Phmmg hinh Schroedinger.
53
Bai 27 - Bang tu�n hoan moi (3)
Gifra th�p nien 1990, trong m9t bai bao dang tren T�p chf Nhfmg kham pha kJ16 tin, giao su Cute
(m<:,t cai ten th�t... d� tlurong!), da cong b6 nhfrng k�t qua nghien cl'.ru v� vi�c phat hi�n dftu v�t
cua m9t n�n van minh ngoai ti-ai d§t, ma 6ng tin r�ng, c6 s\t t6n t� cua nhfmg sinh v� gi6ng con
nguoi. Ong d�t ten cho n6 la Vii tn,1 X. 0 vii tn; nay, h� th6ng nguyen t6 cung dUQ'C xay di,mg
tren 4 s6 hrQ'ng ti'r - nlnmg c6 m9t di�m khac bi�t quan tn;mg. C1,1 th�, d6 la:
n = 1, 2, 3, ...
1 = 0, 1, 2, ... (n - 1)
m1 = -21, -21+1, ..., -1, 0, +1, ... , +21-1, +21
ms = ±½
Hay tht'r xay dµng hai chu kl d�u tien trong bang h� th6ng tuful hoan cua Vii tr\l X. D� thu� ti�n,
hay sfr d1,mg nhtl'ng ki hi�u nguyen t6 cua chung ta cho cac nguyen t6 X c6 cung s6 electron. Vf
d1,1: z = 11 d�u la Na.
54
HU'(mgdiin
Khac bi�t duy nh§t ma ta din chu y la S\f ph\l thuc)c Clla m, vao 1 tang len, dfu1 d�n s6 orbital tang
len. Vf dµ v6i 1 = 1 tltl ta c6 5 orbital, thay vi 3, do d6 s6 nguyen t6 nh6m p se la 10 thay vl 6. Do
d6, ca.c elm kl cua bang tufu1 hoan Vii t:11,1 X se duqc m& r9ng. Gia sir r�ng guy tic Hund vfui phu
l trong bang tu§.n hoan se la (ta v§n sfr dµng kf
hqp v6i vii trµ nay tht c§u true cua 2 chu kl d:u
hi�u cac nguyen t6 & vii t:11,1 cii cho vii tn,1 m&i nay.)
H
[!j I I I
L,
He
@1 I I I
[+J____.__.........___..........,
� I ti I ti
ffI1r ii t I I 1 I r I �t J.!t�1 I r I t I
a
Ne
iTIJJ.lrJ.ltJ.I lrl f!±1t Ir4 J.! t ii 1 I @J t J.I J.!r .11r ii !I
Mg
Al
S1
55
Bai 28 - Bang tu�n hoan moi (4)
H� th6ng tu§n hoan die nguyen t6 h6a hQc ciia th� gi&i ba chi8u ct\a chung ta d\ra tren 4 s6 hrqng
tfr electron: n = 1, 2, 3, ..; 1 = 0, 1, ..., n-1; m1 = 0, ±1, ±2, ..., ±l; va m s= ±½. Hay d�n v&i
F1antlandia, d6 la th� gi&i hai chi8u ma h� th6ng tu§n hoan cac nguyen t6 d\ra tren 3 s6 htQ'ng tit
electron: n = 1, 2, 3, ... ; m = 0, ±1, ±2, ..., ±(n-1), va ms= ±½. m d6ng vai tro k�t hqp ci1a l va
m1 trong th@ gi&i ba chi8u (vf d\1, cac muc s, p, d, ... la c6 lien h� v&i m). Nhung nguyen li co
ba.n va cac cau h6i sau day lien quan d@n th� gi&i FlatJandia hai chi�u, noi ma cac tinh chit If h6a
tu hi�u bi�t ciia chung ta v� th@ gi&i ba chi8u cfu1g dtrQ'c ap d\mg.
a) Ve 4 elm ki diu tien ciia bang tufu1 hoan F1atlandia. Banh s6 cac nguyen t6 theo di�n tfch h:;tt
nhan nguyen tfr. Sir dµng s6 hi�u nguyen tfr (Z) lam kf hi�u cho nguyen t6. Vi�t ciu hlnh
electron cua m6i nguyen t6.
b) Ve cac orbital lai h6a ciia cac nguyen t6 v&i n = 2. Nguyen t6 nao la n�n tang cho h6a hQc
hfm co trong th@ gi&i Flatlandian (sfr dµng s6 hj�u nguyen tfr lam ki hi�u). Tim cac chit
tmmg d6ng trong th� gi&i Flatlandia cho ethane, ethene va cyclohexane. Cac bqp ch�t vong
thO'm nao c6 th� t6n t�i t.rong th� gi&i Flatlandian?
c) Xac dinh cac quy t�c tiro11g duO'Ilg v&i quy ttic bat tfr (6 electron) va t.h�p bat tir (18 electron)
trong th� gi&i khong gian ba chi�u.
d) D\r doan chi�u hu&ng (ve d6 t.hi) bi�n d6i nang lm;mg ion h6a thl'.r nh§t cua cac nguyen t.6
Flatlandjan v&i n = 2. Ve d6 thi bi�u di�n sv tang d() fun di�n ct\a cac nguyen t6 trong bang
tu§n hoan Flatlandia.
e) Ve gian d6 nang luQ'llg orbital phan tfr (gian d6 MO) cua cac phan tir luong nguyen tfr (d�mg
X2) cua die nguyen td v&i n = 2. Phan tfr nao b�n trong th@ gi&i Flatlandian?
t) Xet cac hQ'p chftt luang nguyen td don gian ciia die nguyen td n = 2 v&i nguyen t6 nh� nh§t
(Z = 1). Ve c§u true Lewis cua chung, d\t doan d�g hlnh hQc va d� xu§t ch§t tuo11g dmmg
v&i chung trong th� gi&i ba chi�u.
g) Xet cac nguyen t6 v6i n � 3. D� xu§t m()t nguyen t6 tu011g du011g h'r th@ gi&i ba chi�u va chi
r6 ki hi�u h6a hoc. D,ra vao t-fnh ch§t lf h6a cua cac nguyen t6 tu011g duong, hay dv doan cac
nguyen t6 trong th� gi&i hai chi8u la ch�t rin, long hay khi a di8u ki�n nhi�t d() va ap su§t
thuong.
56
HU'(mgdiin
1)
2
1
1s1
ts 2
3
4
5
I 12; ,
I I� 2
4
[ )2. 2 2p 1 I 12. 22P� I I� 22pJ [ 12. 22p
9
I J 3s 1
15
(
)4s1
6
7
8
10
11
I J3s2
�
I )Js23pl I 13s23p I J 3s23p:i 1 l3s23p'I
19
21
16
17
I J 4s2
d2 J4s23d'3 ( )4s23d'1
I J4 s23d1 J4s23
1
18
20
)4 s23d4
2)
GO
sp1
sp2
Nguyen t6 cua h6a huu C<:i (cua S\1' 6ng): 5.
1--5=5- 1
)
\5-
1\
I
5-5
1--5
\
I
5-5
1/
\
Khong c6 hc;rp ch�t vong thom.
3) Quy t�c sextet (6 e) va 10 e.
57
4o1
12
22
13
23
14
24
(J4 s2� 1 J4s23<f1 ( )4s2 Jd4
4o2
40"
4n3
4)
E
electronegativ1ty
Increasse
3
4
5
6
7
8
Eloment
5) stable= b�n; unstable = kem b�n.
stable
unstable stable
stable
stable
unstable
6)
1
Lew1sstructures
Geomet,y
• 7: 1
3 : 1
0--0 0-0-0
JD-analogs
0--0
FH
LIH
7) g = gas (khf); s = solid (r�n)
58
- -
H
LI
Be
Na Mg
r,
He
g
g
SIC N/0
F
Ne
s
s
AUS P/S
Cl
Ar
s
s
59
rr
s
9
g
g
s
s
g
g
Hoa hoc
• hat
• nhan
Bai 29 - Hoa hQc h�t nhan
1) Gia sir, vao nam 2100, cac phan l'.rng h:;itnhan da gi1'.1p con ngmn kham pha ra duqc nguyen t6
'::,f Mu . Hay cho bi8t san phArn gifra M ll v&i 02, F2, 03 va Hg.
2) Khi mot nguyen t6 phi kim d�ng long phan ra hai h:;it a va mot h�t p+ se thu duqc mot
nguyen t6 A c6 kha nang t:;io phtrc cyanide. Hay cho bi8t phtrc nay c6 mau gl va giai thfch.
3) Nam 1994, ten g9i cua nguyen t6 106 da duqc d� xut'it (v� sau cfmg da duqc cht'ip nh�n) la
seaborgium, Sg, nhb tri an 1lha khoa h9c Glenn T.Seaborg, nguoi da kham pha ra ca.c
nguyen to trans-uraruum.
a) 263Sg duqc t:;io ra b&i s1,r biiu pha h:;it nhan 249Cf b&i chum h :;it nhan 180. Vi8tplnrong tdnh
phan 1'.mg.
b) 263Sg phan ra btrc xa alpha. Xac dinh san phb tao thanh tir phan ra nay.
4) Nhi8u nguyen t6 da. duqc t6ng hqp bfulg each b�n pha cac hat nhan tll'ong d6i n�g v&i cac
h:;it nang luQ'Ilg cao trong cac may gia t6c h�t. Hoan thanh cac phuong trinh hat nhan sau,
duqc sir d1,mg trong t6ng hqp nguyen t6 m&i:
a. ___ • jllc 2i�oi.. 4 c',n
h
•
/._
+ 'l
c.
--- t- 6,1,n
11i r + --- --> Ul'-lDh + 4 1\n
d. l;l� I' + 1�8 _,. ,alLr + ---
60
HU'(mgdiin
1) D\ra vao s\r phan b6 electron c6 th� th§.y nguyen t6 Mu n�m & nh6m IA
13 1
12 2 6
11 2 6 10
2 6
9 2 6
8 2 6
7 2 6
6 2 6
5 2 6
4 2 6
3 2 6
2 2 6
1
10
s
p
10
14
d
f
10 14 18
10 14 18 22
10 14 18 22 26
10 14 18 22
10 14 18
10 14
10
g
h
Nhu v�y khi phan 1mg v&i oxygen se thu duqc h6n hqp oxit Mu20, peroxit Mu202 superoxide
Mu02, con khi phan 1mg v&i ozone se cho ozonide Mu03. San phfun v&i F2 la mu6i floride MF
va v&i Hg se tc;io thanh h6n h6ng (khong xay ra phan ung h6a h9c trong tnrong hqp nay).
2) Nguyen t6 phi kim & d�ng long chi c6 th8 la Brom. Do khong th� xac dinh s6 kh6i ciia d6ng vi
phong xc;t nen t:;un g9i la A. Nhu v�y qua trinh phan ra n1m sau:
ABr ➔33
A-4 A s+a
35
A
A
33-4 As ➔ 31-s Ga+a
8
+
;1- Ga ➔;;s Zn+ p
Nguyen t6 tc;io thanh la kem, nlm v�y phuc cyanide se c6 dc;ing [Zn(CN)4] 2•. Do kem trong phuc
ch�t c6 du hlnh d 10 nen phuc nay se khong c6 mau.
3)
a.
'49
98
Cf t iso
8
b•
,,9
10.S Rf.• '6�
106 sg
4)
C.
!-19
9
f . ,�
-r 7
�60
10S
Db t 4 01 n
d.
61
9
2-19S
er
1S7
unlr + 2 0I n
Bai 30 - Phan ra ph6ng x�
1) ViSt plur011g ttinh cho cac qua b.inh due1c mo ta du&i day:
a) Chromium-51 due1c sir d1,111g lam ch§.t danh d§.u trong t� bao h6ng d.u, phan ra b�ng each
ch1,1p electron.
b) lodine-131, due1c dung d� di�u ui cm:mg giap (tuySn giap ho�t dong qua mtrc), phan ra
t� thanh h�t beta.
c) Phosphorus-32, tich t1,1 trong ph6, phan ra t�o thanh h�t beta.
2) ViSt phtrO'llg b.inh phan ra ph6ng x� cu.a cac h:;i.t nhan sau. (Cac h�t t�o thrum dtr9'C chi r5
trong d§.u ngo�c dcrn, ngo�i trir qua tr'inh bit electron thl electron la tac nhan tham gia phan
1'.rng.)
a) 68Ga (b�t electron)
b) 212Fr (alpha)
c)
62
Cu (positron)
d) 129Sb (beta)
3) Xac din.h h�t bi thi�u trong cac qua trlnh phan ra ph6ng x:;i. sau:
a. 73 G a -+ 73 Gc + ?
l). 19lpl -4 18 Q:,, + '?
c. 105Bi -> 20�Pb + ?
d. 241 Cm I '?-+ 241 Am
62
HU'(mgdiin
1)
b.
a.
131 r
n
+ u1Xe
➔ oe
�
I
C.
2)
a.
6SGa .
C.
?I:! Fr
31
87
Oe
-1
➔
� He +
:!OliA
t
8�
b.
6?
:!9
ti
d.
I :!9
51
b ➔
3)
ti.
7)Ga ➔
nae I- OI e
C.
?OS 81 ➔
+ ti I,;
��� Pb
,1
b\
0"
d.
63
➔ t0i C
61 J'I
:!8
0 C -r I:!� TC
I
$_
oe + 3:!
16
_,
Bai 31 - Hoa hQc h�t nhan
MQt phuong phap da dtrQ'c cong b6 d� t6ng hQ'p nguyen t6 transuranium la boh.rium (Bh) c6 s\r
tham gia ciia qua trlnh b�n pha h:;1t nhan berkelium-249 b&i neon-22 t:;i.o thanh bohrium-267.
a) ViSt plnwng tiinh phan tmg h:;i.t nhan nay.
b) Chu kl ban ra cua bohrium-267 la 15 giay. NSu 199 nguyen nr bohrium-267 c6 th� duqc t6ng
hc.rp th1 sau bao lau se con !:;ti 11 nguyen tu?
c) D\r doan c�u h1nh electron ct1a bohrium.
Hll'61tg d�n
.693 l)l
I n(�] = -kt = -(0.693 l)L • tn(-199_1 )1 = -(015.0
l = 62_7
N0
t1 2
C�u hlnh Clla bohrium la: [Rn]7s25f14 6d5
64
Bai 32 - Hoa hQc h�t nhan
1) TiBn hanh bfu:l pha h,;lt nhan ��2 Cf brtng h,;it �o B thu ducyc 7g� Lr. ViBt phan 1mg xay ra.
2) TiBn hanh b�n pha h�t nhan �8 U b�ng chum neutron t6c do cao thu ducyc h.;i.t nhan khong b�n
9u. H,;it nban nay se nhanh ch6ng pban ra tbanh 239Np r6i h,;it trung gian nay se chuy�n
thanh 239 Pu la nguyen li�u d§.u trong cac lo phan l'.mg h,;it nhan.
a) Viet cac phan img h,;it nhan xay ra.
b) Sau 117 phut, ho,;it do ph6ng X<;l Clla 239 U chi bkg 1/32 so v&i thoi di@m ban d§.u. Hay
xac dinh chu ky ban h11y cirn 239 U.
c) Neu ban d�u c6 lg 239U thl sau 10 ngay se c6 bao nhieu gram 239Pu ducyc t,;io thanh? Cho
rftng sau 5h thl 239 U se chuy�n hoan toan thanh 239Np. Nguyen t6 nay chi c6 th� chuy�n
thanh 239 Pu. C6 th� 1§.y gfu1 dung t112 tinh du<;rc & cau b ap d-µng cho cau c.
23
65
HU'(mgdiin
1) Phan l'.mg xay ra nlur sau: ��2 Cf+�o B ➔ �gf Lr+ 3� n
2)
a)
Cac phan l'rng h:;ttnhan xay ra:
238 U +· n ➔ 239 U
o
92
92
o
239u ➔ 239
+-I
e
92
93
239 N, ➔ 239
pu+0_, e
93 P
94
N.p
b)
G<;>i Ao la ho:;tt do dftu cfia 239U
Sau 117 phtH th1 A= (l/32)Ao tire A= (l/2) 5Ao
Nhtr v�y 5chu ky ban ht1y da qua, m d6 suy ra t112 = I 17/5 = 23.4 phut
c)
10ngay = 240 h, nlnmg trong 5 ti�ng dftu 239u chuy�n thanh 239 Np, tl'rc thoi gian d� 239Np
chuy�n thanh 239Fu la 235h.
Tac6:
O, 6931
2.303 lg mo = At =
m
1112
⇒ m = 0.558g ⇒ mp,, = 0.9442g
66
Bai 33 - Phan ra ph6ng x�
1) M(H lo� may do kh6i thuong ml;l.i ehira mqt luqng nho eh§t ph6ng xc;1 amerieium-241
(241 Am), bi phan ra alpha. Cac h� alpha ion h6a eae phan tir trong khong khf, eho phep
ehung e6 th� d�n di�n, khi cae h:,lt kh6i xam nh�p vao, dq dfin di�n eua kh6ng khi thay d6i va
ehuong se keu.
a) Vi�t plurcrng t:dnh phan ra alpha cua 241 Am.
b) Phan ra hoan toan ctia 241 Am g6m mqt lol;l.t cae phan ra lien k�t: a., a.,�. a., a.,�. a., a., a.,�.
a. va �- Xac dinh san ph§m cu6i cua ehu6i phan ra nay.
e) Xac dinh 11 h:;it nhan trung gian.
d) Chu kl ban huy ctia 241 Am la 433 nam, va 116 phan ra bfulg cac bite Xl;l. eae hl;l.t alpha. C6
bao nhieu h:;it alpha duqc bite x:;i ra m6i gia y b&i 5 .00 gram mfiu 241 Am?
2) Thorium-232 trai qua m◊t ehu6i ph6ng Xl;l. lien ti�p cho d�n khi tl;l.o thanh ehl-208 b�n. M6i
giai do:;111 dm;re chi ra trong bang dmn day, xac dinh eae h:;it duQ'e bite Xl;).:
Parent Nuclide
Particle Emitted
Th-232
Ra-228
Ac-228
Th-228
Ra-224
Rn 220
Po-216
Pb 212
B1·212
Po 212
Pb-208
(Parent Nuclide= hc;1t nban m(;}; Particle Emitted= bc;tt bite xc;1)
67
HU'(mgdiin
1)
::!)7
91
U
?09n·
8.i
? lle + ..·• 1 c, + 83 nt;
241 m
9sA
b.
p
San phfun cu6i la 209
C.
:?JI Am ➔
9\
117 Np+ tl.
9\
2
� Po
-r fi �
1" Pa + <1 ➔
91
:!�: Ili + u �
"·'
U • AI' ➔ �909 Tb + u ➔ �
9�
"" Rn • u
1
�� At +
u � 1;� Fr..,.. <.t � �� Ac + fl
d. Rate = t6c d9; decay= phan ra
k
_ In 2
t 1 ;2
=
0.69315 x I yr x I <l x I h - 5
.08 >' IO 11 s 1
433yr
365d 24h 3600-.
kN _ 5.08 x 10 11. , x S.OO g x
R;llc
I mol x 6.022 x to·.,, nuclc1
241 g
mol
6.35 )( !0 11 decay 1•
2)
2 12 Th
90
a - 1:! I k ➔ 22898 Ac - 0I c ➔ 2...,s Th -r 01 c ➔ :n:n Ra+ 42 lie
➔ ?:!S
88 R
90
11::! P
2 b
68
Bai 33 - Phan ra ph6ng x�
1) D6ng-64 phan ra ph6ng x:;t voi chu kl ban ra 12.8 ngay.
a) Tmh gia tti k theo s· 1•
b) Mot m�u chira 28.0 mg 64Cu. C6 bao nhieu phan ra trong phan d�u tien? Gia sir r�:ng kh6i
lm;mg cua 64Cu la 64.0.
c) Mot nha h6a hoc nh�l dtrQ'C mot m�u 64Cu vt'ra d iSu ch� va do do ph6ng X:;t Ctla n6. Co xac
dinh dtrQ'c r�ng d6i voi mot thf nghi�m, do ph6ng x�khong cttrQ'c xu6ng th§p hO'n 25 % gia tri
do dtrQ'c ba n d§u. Co § .y phai ti�n hanh thf nghi�m trong khoang thcri gia n nao?
2) Mot nha h6a hoc c6 nhu du ti�n hanh mot thf nghi�m v&i 47Ca 2+ (chu kt ban hi1y 4.5 ngay)
dn 5.0 mg h:;it nhan. Tfnh kh6i ltr<;Yng 47CaCO3 d.n phai d�t n�u bi�t r�ng nha cung dp dn
48 gia d� chuy�n hang t&i. Gia sir 1ing kh6i hrQ'ng nguyen tir cua 47Ca la 47.0 LL
3) Bromine-82 c6 elm ki ban ra l.0· 103 phut. N�u b:;tn dn 1.0 gra m 82Br va nha cung c§.p c§n
h
3.0 ngay d� giao hang d�n t'i b:;tn dn d�t bao nhieu gram NaBr (gia sir toan bo Br trong
NaBr dSu la 82Br va kh6i luqng nguyen tir 82Br la 82 u.)?
69
HU'(mgdiin
1)
u. k _
lh
In 2 0.6931 >< �
x
=
t1 2
12 .8d 24 h 3600
_ 6_27 x 10 1 " ,
l mol 6.022x 10 :!3 nuclc1
k
X
b. Rate=- J:6.27x 107. I x(2s.ox10 lg X
J
64.0g
mol
Rate - 1.65 xI 0 1 .a decays/s
c. Sau 2 chu kl ban huy (100%-. 50%-. 25%), thi con l.;ri 25 % luQ'Ilg 64Cu ban d:lu. Do do,
2· 12.8 = 25.6 la khung thoi gian gi&i h<;lll ma co c6 th� ti�n hanh thf nghi�m.
2) Trong bai toan nay, goi mo la kh6i lm;mg 7Ca
4
2+
ban d:lu cfu1 d�t.
J
ln2_
-0.693(2.0d) _
_ -(0.693)t
5 .0µgCa 2+
- k t-----.
k -,I n( - )-.I
I n(------ ------03
mo
,,,2
lo
,, 2
4.5d
.
S O = e-031 = 0.73, mo - 6.8µg
lllo
Kh6i htQ'Ilg mu6i ban d:lu ck d�t la:
3)
kt_
-(In 2)t
,, 2
l.
ln( O
x 24 h x 60 m,n)
-0.69.J3.0 <l
l.
<l
In[ O g1 ..
\.
h
1
m o
1.0 x 10 min
g)
=- -3.0, � = c '·0
mo
mo
Kh6i ht()'J1g bromine-82 c:ln la: mo = 20 gram
20. g ii�Brx
82
l05.0
Br
l mol b2 Br I mot Na 82 Br - g a�-x
-x
= 26 g
82.0 g
mol :!Br
mo) Ja -Br
70
Bai 34 - Phan ra ph6ng x�
1) Curie (Ci) ladon vi tlmcmg duqc dung d@do dQ ph6ng x� h�t nhan: I curie ph6ng x�. b�ng
3.7·10 10 phan ra di�n ra m6i gia y (s6 phan ra tu 1 gram radium trong I giay).
a) Tfnh kh6i luqng cua Nai38 S04 c6 do ph6ng x� 10.0 mCi. Bigt sulfur-38 c6 kh6i hrqng
nguyen tir 38u va chu kt ban huy 2.87 b (gio).
b) C§n bao laud@ 99.99 % mot m§u sulfur-38 phan ra?
2) V1,1 n6 h�t nhan dfiu ti.en dm;rc tign hanh vao ngay 16 thang Sau, 1945 & sa m�c phfa b�c
Alamogordo, New Mexico. D@n ngay 16 thang Sau, 2013 th1 con I� bao nhieu ph§n tram
strontium-90 (t112 = 28.9 nam [yr])?
3) Iodine-131 duqc dung trong chfu1doan va di�u tri b�nh If tuygn giap va c6 thoi gian ban huy
8.0 ngay. N@u b�nh nhan bi b�nh tuy@n giap hiip th1,1 mot m§u Na 131I c6 chl'.ra 10 .0 µg 131 1 th1
sau bao lau hrqng 131 1 con l�i 1/100 so vm band:lu?
4) Technetium-99 duqc sir d1,1ng lam tac nhan ph6ng x� trong xet nghi�m quet xuong (99TC43
duqc hip th1,1 vao Xlto'ng). N@u 99Tc c6 chu kl ban ra la 6.0 gio thl con bao nhieu phlin cua
li�u dl'mg 100 µg 99Tc con Ii trong cCJ th� b�nh nhan sau 2 ngay?
5) Phosphorus-32 la h�t nban ph6ng x::i tlmongduqc dung trong nghjen c1m h6a sinh,dl;tc bi�t la
trong cac nghien cuu v� nucleic acid. Chu kl ban ra cua phosphorus-32 la 14.3 ngay [kf hi�u
d]. Tfnh kb6i lm;mg phosphorus-32 con l� tu m9t mftu 175 mg Na332 P04 ban d:lu sau 35
ngay. Gia sir kh6i hrqng nguyen tfr ciia 32P la 32.0 LI.
71
HU'(mgdiin
1) a)
0.0100
Ix
3.7x10•0 decay� ' 3 .7 10 dcca
Ci
3.7x10·decay = 0.693 l
x lb )x.
Rate=�.
[
2. 7b 3600
9.1x10 1 .?mol a·/' O.ix
m
-
=-.SxJ0'�:uomsof'
O..a = 1.3x10 9 g= I. ng 'a1' 01
1
b) Phan ra 99.99 % thl con lc;ti 0.1 %
(0.6931)t
. t=38 .1 hour �40hour
In(�)= kt= 2. 7h
1.00
2)
n2
t = 6 . 0 yr� k = I :
lI
.?
Con !:;ii 19.6 % 90Sr.
1) 6 .0 yr =
In(�)= kt - -{0.693
1.63, (-o )28.9 yr
o
3)
(0.0 I0) o: t11 = (ln 2)/k
ln( / o) = kt:
0 693
( n )t
ln(0.010 ) - - I l = -< · )l. t
8.0d
l1 2
53 da '
Y
4)
I
n
k- 2:
t 1 ,2
0
In(-) = -k t = (ln 2)t: In(.!!..) = -(0.693)(48. h) _ S.S
0
t 112
N0
6.0h
:'-1 = e s.5 = 0.0041
1'o
Lu0'11g 99Tc con l?i la 0.41 %.
5)
72
e-163 = 0.19 6
175 mg Na/'Po. x
In 2
32.0 mg J2 P
,.. P: k = =33.9
mg
t.,2
165.0 mg a, \�·po ,.
In(-)= -kt= -(0.6931)t. In(
o
t1 2
m
33.9 mg
)= -0.6931(35.0u):
14.3d
Xac dinh kh6i lm:mg phosphorus-32 con l�i:
ln(m)=-1.696+3.523 =1.827. m=c1 ?7 =6.22 mg ':tp
73
Bai 35 - Phan ra ph6ng x�
1) Nu&c mua vira rcri ho�c nu&c tren mM d�t (mr&c IQ thien) c6 chfra du tritium ( 3 H1) d� c6 5.5
phan ra tren m6i phut v&i m6i 100 gram mr&c. Ttitimn c6 chu ki ban ra 12.3 nam. Vao nam
2013, b:;u1 duQ'c yeu d.u ki�m tra tu6i cu.a m(}t lo� nrQ'U c6 duQ'c cho la san xu�t vao nam
1946. B:;m d\r doan duc;rc c6 bao nhieu phan ra tren m6i phut quan sat duc;rc v&i 100 gram
11.fQ'U nay?
2) M(}t cai cay con s6ng c6 chua lm;mg carbon-14 x�p xi nlur trnng carbon dioxide cfia khi
quy�n. Gia su r�ng t6c d9 phan ra quan sat duQ'c cu.a carbon-14 trong cay s6ng la 13.6 xung
[s6 d�m] tren m6i giay tren m6i gram carbon. Se do dUQ'C bao nhieu phan ra tren m6i phut
tren m6i gram carbon tl'r mQt m�u 15000 nam tu6i? Carbon ph6ng Xl;l se dj_nh tu6i t6t v&i cac
m�u nho ca 10 mg, th� chi la nho hon, hay khong? (V &i 14C, t112 = 5730 nam [yr]).
14 12
3) Gia SU �ng ti l� C/ C la hfulg s6, b�ng 13.6 xung tren m6i phut tren m6i gram v6i CO' th�
s6ng. M(}t m�u cay h6a thl;lch c6 1.2 phan ra tren m6i phut tren m6i gram. Tinh tu6i cfia cay.
Cho bi�t v&i 14C, t112 = 5730 nam [yr].
206
23 8
4) M(}t m�u da cln'.ra 0.688 mg Pb tren m6i l .000 mg U. Gia sfr r�g ban d�u khong c6 chi,
toan b9 206Pb duc;rc tl;lo thanh sau nhi�u nam hr 238 U va s6 h<:lt nhan b·ong cac giai dol;l.11 trung
gia n cfia phan ra gitra 238 U va 206Pb dUQ'C bo qua. Tfnh tu6i Clia da. V&i 238U, t112 = 4.5·109
nam [yr].
238
5) Uranium trong t\r nhien duc;rc t,;10 thanh chi1 y�u t1'r U va 235U, v&i ham luc;rng tuO'llg d6i la
99.28 % va 0.72 %. Chu 1d ban ra cu.a 238 U va 235 U 1� hrc;rt la 4.5·109 nam va 7.1·10 8 nam.
Gia su rfulg tu6i hai d�t la 4.5 ti nam. Tinh ham luQng hwng d6i cu.a 238U va 235U khi trai d�t
m6i dUQ'C t,;l.O thanh.
74
HU'(mgdiin
1) decay events = s6 phan ra.
i..1 =
-(0.693)t
I I/ 2
In(-)=
5.5
-0.693(67 yr)
12.3 yr
0.13 decay event
mm • I 00. g water
2)
k
In 2.
II � •
lo(-·)
I c)
kt
(0.693)1 • lo - = -0.693(15,000 yr}
)
(
l1 .?
13.6
5730 yr
D
1.8
Tfnh s6 xung tren m6i phut tren m6i gram:
13.6
- c 1�=-0.17.
-13.6x0.l7-2.3
N�u c6 IO mg C, ta se th�y: 0.023 xungphut. V�y se dn khoang 40 phut m&i th�y du<;1c mQt
xung phan ra (thoi gian nay la qua dai d� cha dQi). Do do, vi�c (ijnh tu6i b�ng 14C khong kha t:hi
v&i cac m�u qua nho.
3)
kt
-(0.6931)1
II 2
In(
1.2 = -(0.693 l)t •
I
)
13.6
5730 yr
2.0 x 10' yr
4) Gia sir c6 1.000 gam 238U trong m§u thl c6 0.688 gam 206u. Do 1 mol 206Pb du<;1c t:;to thanh
tren 1 rnoJ 238U phan ra (decayed) nen:
I mol
I mol Pb
2 8
d - O . 688 g Pb x
X 3 g u - 0.795 g 238u
x
238u uecaye
.I
rnol Pb
mot
206 g Pb
Luc:rng 238U c6 m�t ban d§.u la: 1.000 g + 0.795 g = 1.795 gram
n
9 t
In[ ']- kt- -(l 2)t_ tn(l.000g]= -0.6 3� ) . t-3.8x 109yr
II l
1.795g
4.5 X 10 yr
o
5)
k
ta 2
-(0.693)t
= _ kl =
l1,2
75
9
-' = -(0.693)(4.5 x I 0 yr) = _ _
0 693_
tn(
9
-t5 X )() yr
0 J
= e 0.693 = 0.50
0
-(0.693)(4.5 109 yr)= 4. . _i_ ;:;:
c 4.39 ;:; 0.012
- 39
;:;
In(
:
)
7.1 X )0 yr
0
0
NSu c6 mot m�u hi�n t�i chua 10000 h�t nhan (nuclei) uranium thl c6 9928 hi,H nhan 238U va 72
h�t nhan 235U. Hay tfnh s6 h�t nhan ban d�u c6 n'r 4.5 ti nam tnr&c d� t�o thanh 10000 h�t nhan
uranium hi�n t�:
V&i 238U:
= 9928 nuclei = 2_0 x 10., llN nuclei
- = 0.50. 0 = __
0.50
0.50
0
V&i 235U:
0
72 nuclei
;:; 6.0 x 10, 2·,�u nuc 1 c1
= 0.012 = 0.012
76
Bai 36 - Phan ra ph6ng x�
1 curie (Ci) th, bfulg 3.7· 10 10 phan ra m6i giay (s6 phan ra tl'r 1 gram radium t:rong 1 giay). MQt
m§u nu&c (1.7 mL) chfra tt.itium dtr<;Yc tiem vao mQt b�nh nhan n�ng 150 lb. Ho�t dQ t6ng ctia
bfrc x� dtr<;Yc tiem vao la 86.5 mCi. Sau m9t thoi gian d� cho ho�t d9 tritium phan b6 d�u kh�p co
th�, m9t m�u huy@t tuong chfra 2.0 mL c6 ho�t d9 3.6 µCi da dlr<;Yc l�y ra. Tu nhung du li�u nay,
hay tfnh ph§n tram kh6i hr<;Yng mr&c trong ca th� 150 lb.
Hlt'61tg d�n
Ho�t dQ tiem vao la 86.5 X 10-3 Ci
Ho�t dQ Hiy ra la
i
3.6 XIO Ci
1.8 XI O
--------ml H 0
2.0 mL H 0
6
(i
-:
1
2
Gia St! r�.ng kl1ong c6 phan ra dang k� nao di�n ra, klli d6 th� tfch t6ng cu.a llll'O'C trong mau nhan
v&i 1.8· l o-6 Ci/mL dn phai b�ng v&i ho�t dQ t6ng tiem vao:
VX
l.S XI 0 6 Ci
= 8.65 X IO 2 Ci, V :::; 4.
ml11 .,O
X
Io' ml 1110
Gia sir kh6i hrqng rieng ci1a llll'O'C la 1 mg/mL, phfui tram kl16i hrqng Illl'O'C trong co thB La:
I.OgH 1 0 x lib
ml
453.6g
x 100= 71%
1501h
4.8 x 10.i mLll,O x
77
Bai 37 - Phan ra phong x�
Tu6i cfia miiu da ma con tau Apollo 16 l�y h'r mM trang da duqc xac dinh h'r cac dtr ki en v8 ti 1e
87
Rb/ 86Sr va 87Sr/ 86Sr cila cac loc;ti khoang khac nhau c 6 trong m§.u da.
Khoang
87Rb / 86Sr
87 Sr / 86Sr
A (Plagioclase)
0.004
0.699
B (Quintessence)
0.180
0.709
a) 87Rb phan ra p, vi8t phan ung phan ra nay. Chu ky ban hily cua phan ra nay la 4.8 x 10 10
nam.
b) Tfnh tu6i ci1a m§.u da. Bc;tn c6 th� gia sir r�g ti 1e 87Sr / 86Sr ban dfiu la nlm nhau trong ca A
va B, 87Sr lfu1 86sr d8u b@n vung.
Hll'&ng d§n
a) �Rb➔ !�Sr+�, p
b) 87Sr Jue nay = 87Sr,=0 + 87Rb1=0 - 87Rb1ucnay
87
Rb1ucnay = 87Rb1=0 exp(-11,t)
(
Rb 1=0/ 87Rb1uc nay)= exp(11,t)
87
Sr lucnay = 87Sr1=0 + 87Rb1ucnay(exp(11,t)- 1)
87
(
S r lucnay/ 86Sr) = (87Sr 1 =O / 86S r) + (87Rb1ucnay/ 86Sr)(ex p(11,t) - 1)
87
y
=
C
+
x(rn)
Trong phep tfnh g§n dung th.i (87Sr iuc nay/ 86Sr) v6i Ava B nlnr nhau
m = (0.709 - 0.699) I (0.180 - 0.004) = 0.0568 = (exp(11,t) - 1)
11.t = ln(2)t / t112
tin= 4.8·10 10 narn
t = (4.8·10 10)111(1.0568)/ ln2 = 3.8· 10 9 nam
78
Bai 39 - Phan ra ph6ng x�
Cobalt-60 ph6ng x� duqc dung d� nghien ciru cac khiJm khuyJn trong h§p th\1 vitam1n B12 b6'i
cobalt I.a nguyen tfr kim lo:;i.i nfun 6' tam phan tfr vitamin B12. T6ng hqp h�t nhan cu.a d6ng vi
cobalt nay la qua hinh 3 giai do�n. Phan irng t6ng la sit-58 phan ung v&i 2 neutron t:;i.o thanh
cobalt-60 d6ng thc'Yi buc x:;i m9t vi h:;it khac.
a) Xac dinh vi h:;tt duqc buc x:;i ra.
b) Tinh nang hrqng lien kJt theo J tren mdi nucleon ciia h:;tt nhan cobalt-60 (kh6i luqng nguyen
tfr cobalt-60 la 59.9338 u; hydrogen-I la 1.00782 u.)
c) Tinh bu&c s6ng de Broglie cila h:;it buc x� biJt t6c dQ ciia n6 b�ng 0.90 lftn v�n t6c anh sang.
79
HU'(mgdiin
a) Vi h:;it con thi�u la electron.
b) Nguyen ti't 6°Co c6 27e, 27p va 3311. DQ h\lt kh6i cua h�t nhan 6<JCo la:
Ill = (59.933
1
ll"lc) 33( l .00866)] = - 0.5631 U
27n1c) [27( J .00782
E -.. mc = - 0.5631 u x
1.6605 X IO �7 kg
------ X
(2.9979 X JO m/ )1 =- 8.403 X JQ II J
Nang hrQ'Tlg lien k� t tren m6i nucleon la:
8.403 X 10 II J
60 nucleons
------ = 1.40 I x IO 12 J/nuclcon
c) H:;it buc x<,1. la electrnn, c6 kh6iluc:mg 9.109·10-31 kg. Bu&c s6ng de Broglie la:
h
A.=­
lllV
34
6.626 X IO J s
---------------= 2 . 7 X I 0 12 Ill
9.109 x 10 31 kg x (0.90 x 2.998 x 108 m/)
80
Bai 38- Phan frng h�t nhan
Cac d6ng vi ph6ng x� c6 th� duQ'c dung trong cac chfin doan y l19c va chua b�nh ciing nlur dt\ng
trong phan tfch cong nghi�p. R§t nhi8u d6ng vi ph6ng x:;t nlur P-32 (M = 32) va Co-60 c6 th�
dung lam ngu6n phat neutron trong cac thi�t bi phan rrng h�t nhan. Tuy nhien m9t s6 d6ng vi
ph6ng x:;t n,r nhien nlnr C-14 va T-3 (triti) c6 th8 dm;rc t:;io thanh b�ng each b�n pha d6ng vi N-14
trong khf quy�n bfulg cac ti.a vt1 tn,1 (S6 hi�u nguyen tu cua 3T, 1 H, 14C, 14N, 32P, 60Co va neutron
1
n l§n luQ't la 1, 1, 6. 7. 15, 27 va 0, t(rc P-32 c6 th� dtrQ'c vi�t la �; P.
1) Vi�t cac phan irng h�t nhan xay ra khi bful pha d6ng vi N-14 trong khf quy8n bfulg neutron
d�n tu tia vt1 tn,1 d8 thu duqc C-14 va T-3 va phan l'.rng t:;io thanh P-32 khi chi@u x� P-31 b�ing
neutron trong thi@t bi phan li'ng h�t nhan.
2) D6ng vi ph6ng x� P-32 c6 m<'?t vai tro quan trc;mg trong cac nghien ciru sinh hc;>c v&i chu ky
ban hi1y t112 la 14.3 ngay. D6ng vi ph6ng x� P-32 c6 th8 duqc dung d8 xac dinh th8 tich mr&c
trong h6 boi hay th8 tich rnau trong d9ng vat. 2.0 mL dung dich chufui chl'.ra P-32 v&i d9
ph6ng x� 1.0 Ci/ rnL duqc dua vao h6 boi. Sau khi tr911 d8u thi ho�t d9 Ax cua 1.0 mL mr&c
trong h6 boi dm;rc xac dinh la 12.4 cpm (1 Ci= 3.7· 10 10 phan ra / s). Tfnh th8 tich mr&c trong
h6 boi.
81
HU'(mgdiin
1) Cac phan l'.mg:
2) T6ng lm;mg P-32 la mot h�.ng s6 va 116 duqc gift nguyen tru6'c va sau khi dua vao h6 boi
Nim v�y V oA o = Vx A x , v6'i V o va Ao la th� tfch va ho�t d() cu.a dung dich ch uful
vx va Ax la th� tfch va ho�t d() cu.a h6 boi sau kiri dua d6ng vi vao.
Nlm v�y 2.0· l.O = V x.12.4 / (3.7· 10 10) ⇒ V x = 5.97· 109 mL = 5.97· 106 L
82
Bai 37 - Phan ra ph6ng x�
D6ng vi nhan t�o �Co duqc dung trong y t� phan ra thanh d6ng vi b8n la :Ni.
1) Vi8t cac plm011g binh phan img h<;1t nhan xay ra.
2) Bi�t chu ky ban hi1y ��Co thanh :Ni la 5.33 nam. Hay tinli:
a) Kh6i lm;mg �Co dA c6 do ph6ng x<;1 la lOC
b) Sau khoang tbai gian t rn�u ch§t ph6ng x� c6 ti 1� kh6i luqng :Ni so v&i �Co la 0.9
(coi t:rong m�u khong c6 san phfun trung gian). Tinh t.
83
HU'(mgdiin
a) Phmmg hinh phan ra.: � Co ➔ � Ni + -� e
b) ChQnt= 0 lathoi di�m m�u ph6ng x� �Co c6 do ph6ng xi;i la 10 Ci,ta c6:
°·
693
11,
o = --· N o
D"Q ph'ong xi;1 b an d;.,au: Ho = '\N
T
S6 nguyentfr ban fulu c6trQng luQ11g ph6ng xi;1: No =
0 693 m
m
o . N A ⇒ Ho= ·
. o .N A
T Ac
Ac.,
0
Ho ·T· A 10·3.7·10'0 •5.33·365·24·3600·60
=
⇒ Ho = mo =
,
o.693. NA
o.693. 6.022.10-3
= 8.94- 10· 3 (gram) = 8.94 (mg).
S6 nguyentfr :Ni t:;iothanhsauth<'Yi giant phan ra bfulg s6 nguyentfr :co bi phan ra
·A
lt
. .
m ·A .
nikens inb ratrono0th'
⇒ Kh;.01. 1uono
0'1 e,·
01ant: m N,. = �N N.' = o N' • (1 - e· ) (1)
. e,
NA
ACo
Mijt khac khdi lm;mg coban con l:;tisauthm giant phan ra la: mco = mo.e· At
Tll' (l) va (2) ⇒
1
⇒t = -ln(
1
mNi
A
-1
= Ni ·(e ll )
ffico
m , · Ae
N,
Aeo
T
0.693
o + 1) = --· ln(
111 e.o · A Ni
m ·A
5 33
60
+ 1) = -· -ln(-·0.9 + 1)
0.693 58
111c0 • ANi
N;
e.o
t = 5.06 nam
84
(2)
Bai 40 - Phan trng h�t nhan tren m�t troi
1) M�t trO'i bt'.rc X:;l khoang 3.9· 1023 J nang ltrQ'ng va.o vii tr\l m6i giay. Tinh t6c d9 S\lt giam kh8i
ltrQ'llg cua M�t tr6'i.
2) M6i giay Trai d§t nh�n l.8· 10 14 kJ nang lm;rng m�t tr6'i. Tinh kh8i luQ'llg v�,t li�u m�t tr6'i
chuy�n h6a thanh nang luc;Yng trong chu ki 24 gi6' d� cung di.p nang luQ'llg hang ngay cbo trai
d�t. Tinh kh6i hrQ'ng than da c§n d6t chay d� cung dp nhi�t hrong nlm b.-en, cho bi�t m6i
gram than da khi d6t giai ph6ng 32 kJ nang hYc;Yng.
85
HU'(mgdiin
1)
- E - 3.9 X I o2J kg m 2 ,s 2 - 4 3
A
A
el
- . )( I 0<1 kg
u
"E = um , uln - -, - 3
c"
( .00 x IO m/ )",
V�y m6i giay kh6i hrQ'ng m{lt trai giam di 4.3 nghin t§n.
2)
t.8 x IOu kJ x 1000.l
kJ
x
3600s
24h
_ 1.6 x 10.,, J/day
x
h
day
n
1.6 x Io-- J
=., = ------8
1
c-
(3.00 x l 0 m/s)
= 1.8·105 kg
Lu<;rng than da tmmg frng dn dimg la:
t .6 x Io� J x
1
1 J
k x _!_L x kg = s.o x 10 1 " kg
I 000 g
1 000 J
3 2 kJ
86
,
,
Cau true phan tir - Thuyet MO
Bai 41 - L\fC lien k�t
Hay tinh hrc finh di�n va htc h§.p dfui gitra hai ion Na+ va ci- c6 khoang each 280 pm.
h_rc finh di�n F = K q 1�2, K = 9.0 · 109 N · m 2 • c- 2
r·
Hmrngdi\n
Li,rc b§.p dfui
m m2
F=G , 2
r
2
_, (23x35)x(1.6x10- kg )
. _11
.N•m-•kg - )
= ( 6.7x10
10 2
2
(2.8xl0 ) m
,
27
= l.76x10-43 N
Li,rc finh di�n
= 2.94x 10-9 N
C6 th� th§.y r�ng 11,rc finh di�n trong tnrcmg hqp nay l&n han r§.t nhi8u so v&i l1,rc h§.p dful, do v�y
trong thi,rc t� c6 th� bo qua 11,rc h�p dful.
87
Bai 42 - Nang hrQ'llg lien k�t
BiSt nang hrQ'llg Lien kSt Clla phan tfr Ch la 243 kJ mo1- 1, nang luQ'llg ion h6a thl'.t nhfit Clla nguyen
tu Cl va phan tir C'2 lftn luQ't la 1250 va 1085 kJ mo1- 1• Tinh nang luqng Lien kBt cila Ch+ va thao
lu� ti�u phan nao (Ch hay Ch+ ) c6 lien kM dai hem. Giai thich.
Hmrngd�n
0 0.1013 MPa va 298 K, nang hrQ'ng phan li lien kSt cua phan tu hrcrng nguyen tu (nang hrQ'llg
lien kSt cua n6) c6 th� xac mnh tu cac do hr6'ng nhi�t h6a hQc. The o nguyen If tht'r nhfit nhi�t
d9ng hQc, su dt,mg cac du ki�n duQ'c cho trong cau heh nay, ta c6 chu trin.h nlnr sau:
ra�CJ.C].
Cl+C
Cl�
- -Ic_1-!.,_ Cl +Cl ++e
�c ·
'2
l
-
::: 242kl•mor' +1250kJ•moZ- 1 -1085kJ•moZ- 1
::: 407kJ •moZ- 1
Tu kBt qua tinh toan c6 th� th§y d.ng nang hrqng lien kSt Ch+ 16n han Ch b&i Ch+ c6 it han 1
electron phan lien kSt so v&i Ch, dfu1 dSn bac lien kSt cao hon (1.5). DI nh.ien, con cac nguyen
nhan khac la d.i�n tfch hi�u di,mg cua Ch+ Ian hon Ch va mire do xen ph11 ct\a cac orbital nguyen
tfr l&n han.
88
Bai 43 - Nang hrQ'llg lien k�t
Enthalpy t�lO thanh cu.a H202(g) la .:1Hr = -133 kJ mo1- 1, nang lm,rng lien k�t 0-H la 463 kJ mol 1
va nang lm;rng phan li H2 , 02 l§n hrqt la 436 va 495 kJ moi- 1. Tinh nang hrqng lien k�t 0-0 trong
H202.
Hmrngd�n
Phan ung t�lO thanh H20 2 :
Mi 1 = -133kl •mor'
= 436kl •mor 1 + 495kJ-moZ-' -2 x 463kJ •nwZ- 1 -(-133kJ •moZ- 1)
= 138kJ•mor'
89
Bai 44 - Moment quan tinh
Phan tit CO2 ( 12C, 160) c6 moment quan tfnh la 7.167 · 10-46 kg· m 2•
a) Tinh d() dai lien k�t C=O trong phan tu CO2 .
b) Gia su r�ng S\t thay th� d6ng vi khong anh lm&ng d�n d9 dai lien k�t C=O, tmh moment
quan tfnh cua phan tu CO2 chl'.ra 12C, 180 va 13c, 160.
Cho bi�t moment quan tfnh ciia m()t phan tit th�ng c6 th� duqc tfnh theo cong thl'.rc:
m11m8 t'1n + m8mc''ic + m11 m8 ( "iIB + r8c )
f=-------------------ml\ +m8 + me
2
90
Hmmgd�n
a) Do ti·Qng tam va tam d6i xirng cua phan tu CO2 trung nhau, nen nguyen tu C k.h6ng c6 d6ng
g6p vao moment quan tinh Clla phan tu, do d6:
2
= (7.167 X 10- kg•m X3 6.022x10
2xl6x10- kg•mor1
46
23
mor1
)
:::1.16lxl0- 10 m
b) Gia sir dmg s1,r tbay th8 d6ng vi khong fu1.h lur&ng d8n de'.> dai lien k8t C:::O, ta c6:
:::
2x (18x10- 3 kg•mor 1 )x (1.161 X 10- 10
6.022x10 23 mor'
= 8.058x10-46 kg•m 2
mt
DO nhfrng nguyen n.han da chi ra & d�u y (a), moment quan tinh Ctla 13 C 16O2 va 12 C 16 O2 b�ng
nhau.
91
Bai 45 - Cfiu true phan tir
T� sao c6 OHt va NH4+ n.lumg kh6ng c6 CHs+ ? T� i sao SF6 t6n t�.i con OF6 thl kh6ng?
HU'(mgdin
Theo thuy�t lien k�t c(>ng h6a trj va thuy�t orbital phan ttr, s6 lien k�t m(>t nguyen tu t�o thanh
chtl y� u ph\1 thUQC vao s6 orbital nguyen tir ma nguyen tir d6 c6 th� cung dp phu hQ'p v&i di�u
ki�n t�o lien k�t. C, N, 0 la cac nguyen t6 thu(>c chu kl 2 va nguyen tfr cl'.ia chung chi c6 4 orbital
h6a tri, va t6i da chi t�o thanh 4 lien k�t don c(>ng h6a tti. Chfnh b&i v�y, OH3+, � + c6 th� t6n
t� nlnmg CHs+ va OF6 thl kh6ng.
V&i cac nguyen t6 thu(k chu kl 3, nguyen tir c6 9 orbital h6a t1i va v� m�t li thuy�t thl c6 t6i da 9
lien k�t dO'll c(>ng h6a tri c6 th� duqc t�o thanh. Tuy nhien, orbital cl c6 tham gi a hi�u qua vao
vi�c t�o lien k�t hay kh6ng tuy thu(k vao SlJ phan b6 (s�p x�p) dia n6. N�u cac orbital d bi phan
tan va each xa h�t 11.han, thl hi�u qua t�o lien k�t kem, tMm chf khong th� t�o lien k�t. V &i
tnrc'mg hop SF6, thl cac orbital d tham gi a hi�u qua, va ban kfnh ctia S l&n nen du kh6ng gi an
xung quanh d� chira 6 nguyen tir ph6i trf. Do d6, SF6 c6 th� t6n t�. Phan tir nay c6 du tnk bat
di�n d8u va thuoc nh6m d6i xl'mg di�m Oh.
92
Bai 46 - Thuy�t VSEPR
Xac dinh s\r s�p x�p trong khong gian cua cac c�.p electron trong cac phan tfr sau:
(a) /CL;- '
N2 O
(b)
H3O+ ' BrF;. ' NF3
(c)
,er
4
(d) IF;. '
TF4+
SbF4
XeO2 F2
XeR,+ 0
93
HU'(mgdiin
(a)
0
H
•
Cl
Q
F
(b)
(c)
(d)
94
Bai 47 - Thuy�t VSEPR
Sir d1,111g thuy�t sire d§.y cac c�p electron h6a tri dt dµ doan d:,mg hlnh hQc cu.a die phan tfr sau:
Xef:i ,XeO 4 ,XeO3 ,XeF2 ,XeOF4
Hll'611 g d§n
XeF4
XeO4
XeO3
XeF2
XeOF4
6
4
4
5
6
S�p xep khong gtan cu.a cac
Bat di�n
electron h6a tri
Tfr di�n
Tt'.r di�n
Lm:rng thap
Bat di�n
tam giac
C�p electron chua lien k�t
2
0
S6 ph6i trf
4
4
Dc;lllg hlnhhQC
Vuong
phfu'lg
Tfr di�n
Phan tfr
m+n
95
3
I
3
2
5
Ch6p
tam giac
Tb�ng
Chop day
vuong
Bai 48 - Thuy�t VSEPR
Sir d\mg thuy�t sire d!y cac c�p electron h6a tri d� d\l' doru1 dc;lng h1nh hQc ctia cac phan tfr ho�c
ion sau va cho bi�t pha:n tir nao moment luong qrc:
AsH3 ,CIF; ,S03 ,SO�· ,CH; ,CH3
Hlt'611 g din
Phan tu ho� ion
AsH3
CLF;
S03
so32
CH3+
CH-3
m+n
4
5
3
4
3
4
-
S�p x�p khong
Ttr
gian ctia cac
di�n
electron h6a tri
Luong
Tam giac Tfr
thap tam
di�n
phfuig
giac
C�p
electron
cJma lien k�t
l
2
0
1
0
1
S6 ph6i trf
3
3
3
3
3
3
D:;ing hlnh h9c
Chop
tam
giac
Chop
D�g chu Tam giac
tam
pbang
T
giac
Co
C6
Moment
luong
C\l'C
.
Tam
giac Tu
phing
di�n
Tam
giac
ph�g
Chop
tam
giac
Khong
5 cijp electron hoa tri quanh nguyen tit Cl trong phan tu ClF3 duqc phan b6 (s5p x�p) theo d:;tng
hrang thap tam giac, v&i 3 dc;tng hlnh h9c kha cu:
F F
:-Cl
I'\..
F
(A)
Ip-Ip
.. F
I '\ p
F
F-Cl
I_ _'\F
I/
:-Cl
j/
3 d:;ing s�p x�p
.. F
I/
(C)
(B)
0
1
0
Jp-bp
4
3
6
bp-bp
2
2
0
*Ip = lone pair (c{lp
clma lien k�t); bp =
bonding pair (c{lp lien
96
k�t)
,
I
So sanh (A) v&i (B) thi (B) c6 hrc day lp-lp (giua cac c�p khong lien ket) thay vi tu011g tac lp-bp
(giua c�p lien k�t v&i c�p kh6ng lien k�t). Do d6 (A) b�n hon (B). So sanh (A) v&i (C) thi (C) c6
them 2 tuong tac lp-bp thay vi 2 tu011g tac bp-bp (giua cac c�p lien k�t), do d6 (A) b�n nhfit.
97
Bai 49 - Thuy�t VSEPR
Da c6 th6'i kl, cac khf hi8m dtrQ'c xem la b:O' hoan toan va kh6ng c6 kha nang t�o thanh lien k8t
hoa hQc. Ngay nay, chung ta da bi8t k8t lu�.n nay la kh6ng chinh xa.c, va trong da s6 giao tr1nh
Hoa d� cuong d�u c6 nh�.c d�n m9t s6 hqp ch§t chl'.ra layption va xenon da dtrQ'c phan lap.
a) D\ta vao thuy8t lien k8t hoa tri, hay d\t doan cac c§u tru.c h1nh hQc c6 th8 c6 cua XeF2 va
XeF4.
b) Xac dinh s6 oxid boa cua Xe trong cac hqp ch§t nay. D\t doan chimg c6 tinh khit hay tfnh
oxid hoa.
c) Helium duqc cho la nguyen t6 "t:rO'" 1th.§t. Tuy nhien, tinh 1:rO' cua helium cung chi ap d\mg
cho cac hrong tac cua n6 v&i nguyen tit va phan tu trung hoa. Cac hqp ch§.t cua helium - v&i
nhfmg lien k�t hoa hQC th6ng thm'mg dtrQ'C t,;10 thanh tl'r helium va cac nguyen tit khac - c6
th8 t6n t,;li khi toan ti8u phan mang di�n (tlm6'ng la di�n tich duO'Ilg.) Vi d\l, nguyen tit helium
c6 th8 t�o thfulh cac hqp ch§_t quan sat dtrqc (kh6ng nh§.t thi8t phai t6n t�i lau) v&i H + , He+ va
He2+ . Sit dl)ng thuy8t MO d8 xac dinh bac lien k8t trong nhfmg tnrcrng bqp nay.
d) Nhin clnmg, cac clication lmmg nguyen tu b�n c6 c6ng thirc XHe 2+ chi t6n t,;li khi IE(X+) <
IE(He): nglua la khi nang luQ'ng dn d8 ion hoa ti8p x + be h011 nang ltrqng ion boa He.
Khong cfin d\ta vao bang cac mfrc nang hrQ11g ion hoa, hay xac dinh nguyen t6 "Z"nao, b:ong
khoa . ng tt'r H d�n Ar, phu hqp v&i tieu chufu1 nay.
e) Nguyen t6 nao, k8 can v&i nguyen t6 Z da xac dinh & tren (nglua la nguyen t6 k8 ngay ben
trai, ben phai, ben tren hoijc ben dtr&i, trong bang h� th6ng tufu1 l10an) la. cung phu hQ'P d8 t�
m9t dication b�n v&i He? Nguyen t6 k� can v&i Z nao la kh6 t�o dtrqc clication nlm tren nh§t?
98
HU'(mgd�n
a)
.. . .
:p:xc:f:
... '. ..
:f:
:f:xe:f:
.. . , ..
••
Ill
l1
II
•"
: F:
Trong XeF2 thl Xe c6 5 c�p electron, do v�y n6 c6 du true xay d1,mg d1,ra tren c§.u tn'.1c hrong
thap tam giac. Trong 3 kha nang
F
I
I
F-Xe
F
F-Xe-F
F-Xe
thl d.u true thfulg giam dBn t6i thi8u 11,rc d�y gii'l'a cac c�p electron clnra lien k�t (chung se g§n Xe
h011 cac electron trong cac lien k�t Xe-F). Do v�y c�u true thing tm ti.en h011.
Trong XeF2, Xe c6 6 c�p electron, v&i c§.u true xay d1,rng dµa tren c�u true bat di�n. Trong hai
kha nang
F
F
F-Xe-F
F-Xe-F
I
I
I
F
�F
C§u t:;i,o phing lam giam d&n t6i thi8u 11,rc d§y ciia c�p electron chua tham gia lien k�t nen la du
trtlC duc;rc lffi ti.en h011.
b) F luon c6 s6 oxid hoa -1. Do v�y s6 oxid hoa ct\a Xe ta +2 (XeF2) va +4 (XeF4). Cln'.lng d�u la
nhung ch§t oxid hoa r§.t m:;mh.
c) Bo qua sµ khac bi�t v� mire nang hrc;rng gifra H va He, chung ta c6 th8 ve cac gian d6 MO sau
day:
Is
,, ... ,, .
.. 4
.
.
..
" f,
rf'
,,
•••
He
ls
H+
CJ
a'
ls
c.
He
ls
,;
He
111
..
..
..
..
c '· ... ••
.. _ Iii Iii 1111
�
� #-
CJ
,
f
.... ..
ls
He+
rt'
.,.,
ls
..
.............
CJ
He2+
99
Tfr cac gian d6 nay, d� thfty rfu1g HeW va H� 2+ d�u c6 b�.c lien k�t bfulg 1, con He2+ c6 b�c lien
k�t 0.5.
d) Cac nguyen t6 nh6m II se c6 nang lm;mg ion hoa thl'.r hai th§p (b&i Be ➔ Be2+ hay Mg ➔
Mg2+ d�u t�o ra l&p v6 kfn, c6 du hinh "kltl h.i�m" 1s2 ho�c 1s22s 2 2p6 .) Mg2+ c6 hi�u l'.mg chin
t6t h011 Be2+ nen IE(Mg+) < IE(Be+). Do v�y Mg la phu hqp ch§t v6i "Z".
e) Trong cac nguyen t6 k� c�n Mg (Be, Na, Al, Ca): Ca c6 nang luqng ion h6a thu hai thflp nJ1§t
trong v1 nhrrng li do ttr011g t\r da neu tren. Nen Ca tltlch hqp nhftt dA t:;io dication b�n v&i He.
Na+ da c6 l&p ngoai cung bao hoa, nen r§t kh6 xay ra qua trmh Na+ ➔ Na 2+. Vl v�y, kha nang dA
Na ti;i.o dication v&i He la thftp nhftt.
100
Bai SO - Thuy�t VSEPR
Trimetylphosphin e6 tha pha.n l'.mg dm;re v&i SbCh t�o thanh hai h<;rp eh�t e6 cong thire
(Me3P)(SbCh) va (Me3P)2SbCb. Hay ve c�u true khong gian cua hai h<;rp ch�t na y dl,la tren
thuy�t VSEPR.
Hmrngd�n
C!iu
. true khong gian d1a hai phirc
Cl
PMe3
I
•
I
:.::::-Sb, :
1--- PMe
7!.
--/Y1
--
--�
I
C!�-f
: /Sb, :
I/
I ........ I
---- ---- I
Cl
3
Cl
1
C
PMe3
Trong ca hai h<;rp ch§t nh6m Me3P phai & xa c�p e nh�t da giam t6i thiau tuong tac d�y. 0
(Me3P)2SbCh hai nh6m PMe3 phai & hai vi t.rf tn..ic vi tirong tac khong gian & hai vi bi d6 giam
d�n mire t6i t.hiau.
101
Bai 51 - Str lai hoa
Xac dinh d�ng hlnh h<;>c va lai h6a ci1a nguyen tfr trung tam trong cac phan tir hoi,ic ion sau:
CS 2
,
No;
t
No;
•
,
BF;
,
CB'4
PF4+
Hmrngdin
Phan ti'r hoijc ion
D�ng h1nh h<;>c
Lai h6a cu.a nguyen tfr
trung tam
CS2
Thfulg
NO2+
sp
Thfulg
sp
NO-3
Tarn giac
sp
BF;
Tarn giac
sp 2
CBr4
Tu di�n
sp 3
pp+
4
Tu di�n
sp 3
SeF6
Bat di�n
sp3 d 2
SiF;-
Thap day vu6ng
sp3 d
AlF.53
Bat di�n
sp3 d2
IF6+
Bat di�n
sp3 d 2
MnO;
Tu di�n
sd 3
MoCl5
Luang thap tam giac
d3sp
( CH 3 )2 SnF2
T-1,ra tu dj �n
sp3
102
2
Bai 52 - Cfiu true phan tir
Bang duoi da.y cho bi�t thanh ph§.n trung bhlh ciia khf quy6n (ppm = parts per million [ph§.n
tri�u]). Hoi. llltO'C cung c6 mM v&i lttQ'Tig nh6 va ham lm;mg bi�n d6i.
(:as
lie
e
Ar
Kr
C
H,
,
01
Average
Ga.
S.2
Cl 1 1
11moun&/ppm
IS
9340
I I
0.09
0.58
7�0R40
209460
0
CO:
20
NO
0,
o,
NH 3
A"crage
amount/ppm
1.72
012
355
0 31
<0.01
0.1 0.0 I
<10 4
<..10 J
(gas = klri� average ammount = ham hrQ'Tig trung b1nh)
a) Ve d.u true Lewis ciia N20, dam bao rftng m6i nguyen tit d�u tuful theo guy tic bat tir.
b) Sit d\mg m6 hinh VSEPR d6 d\l doan hinh d�ng phan tt'l cim SO2, NH3, N2O, CR4, CO2.
c) Khf nao trong bang la g6c? V&i m6i khi dm;rc chon, hay giai thfch s\r xu§t hi�n cua tfnh chftt
g6c.
d) 03 (ozone) chi t6n tl;l.i voi ham luQ'ng < 0.1 ppm, tuy nhien 116 la m9t thanh ph§.n thi�t y�u cua
khf quy&1 Trai d§t. T:;ii sao?
e) Ve gian d6 MO bi6u diSn s\r t:;io thanh phan ttr N2 tu 2 nguyen tfr N. Sir d\mg gian d6 d6 giai
thfch t� sao N2 c6 tinh trO' v� m�t h6a hoc.
t) Xac dinh m6i lien h� giua cac klri dO'll nguyen ti'r trong khf quy6n Trai d§.t.
103
HU'(mgdiin
a) C§.u true Lewis ctia N20:
=== +·==o
+
◄-►
-o
b) D�ng h1nh hoc ci1a cac phan tfr:
S02
NH3
phan tf:r bi be thap tam giac
cong
N20
CH4
CO2
thfulg
tl'.r di�n
th�ng
c) Cac ti�u phan g6c la 02 va NO. Mijc du 02 c6 s6 electron chan nlnmg cac MO cao n.h§t la
nhtmg orbital suy bi�n va bi chi�m b&i 1 electron, dfu1 d8n 02 la mot g6c d6i. NO la g6c b&i 116
chua s6 electron le (11 electron h6a tri) va HOMO la orbital bi chi8m b&i 1 electron.
d) 03 h§p th1,1 cac tia trong vung UV (ci,rc tun). S1,r hi�n di�n ct1a n6 trong khf quy�n Tcij d§t la
d.n thi�t cho si,r bao v� b8 mM trai d§t khoi s1,r chi8u x� tia UV qua muc t1'r M?t troi
e) Gian d6 MO ctia N2. Gian d6 nay cho th§y b�c lien k�t giua hai nguyen ttr N la 3. Do d6 day
la lien k�t r§t b8n (945 kJ/mol) va kh6 bi pha vfJ, chfnh v�y nen nitrogen ttrong d6i b:O' v8 m�t
h6a hoc.
l
r
2,,
2p
i2
g) Cac khi d011 nguyen tu (He, Ne, Ar, Kr, Xe) d�u thuqc nh6m khf hi8m.
104
Bai 53 - Thuy�t MO
Ap dµng thuy�t orbial phan tfr (thuy�t MO), hay chi ra hj�u frng (anh lurO'llg) cila m6i qua trinh
ion h6a sau day toi do b�n lien k�t cila phan tfr tuong 'frng:
c)
NO
�
o +2 '
�
N;;
�
NO+ + e.
105
HU'(mgdiin
a) D6i v&i qua tlinh
02 -► 02+ + e:
Ttr gian d6 nang hrQ'llg va k�t qua S\f diSn (s�p x�p) electron vao gian d6 d6, ta c6 c�u hinh e ctia
4
1
1
1r*.t 1r*)' • Bae
lien k�t 11 = (8 - 4)/2 = 2.
02 la [KK] a-.f2 a-','i 2 a-z2 1r:r.y
.
Trong qua tr1nh 02 - e -► 0;. ch�ng h:;m electron nay rn�t m MO- n; nen du hinh electron cfia
o; la [KK] a-,;a-_: a-;1r.:.y1r.: 1r;�. Tt'r d6 0; c6 b�c lien k�tla n = (8-3)/2 = 2.5.
2
1
B�c lien k�t trong 02+ (2.5) 16n h011 trong 02 (2) do d6 qua binh ion hoa nay lam cho lien k�t
trong ph�n fir bSn h011.
b) Ta xet tu011g ti,r nlur hen cho qua binh: N2 + e -► N f. Tt'r gian d6 n ang hrqng va k�t qua
s\r di�n elecb·on, ta c6 du hinh electron ctia N2: [KK] a-;a-:2 1r.:.ya-;; l'.mg v&i b�c lien k�t la.
n = (8 - 2)/2 = 3. Khi N2 nh�n them 1 elecb·on, c�u hinh electron ti·& thanh
[KK] a-;a-;n_:_>'a-;n_:\ v&i b�.c lien k�tla n = (8 - 3)/2 = 2.5.
B�c lien kM giam lam cho d◊ b�n ctia lien k�tgiam.
c) D6i v&i qua binh NO -► NO+ + e: B�ng each ly lu�n tuO'ng ti,r th§.y rfu1g b�c lien kM trong
NO la 2.5, con trong NO+ la 3. Qua tr1nh ion hoa NO thanh NO+ lam tang d◊ b9i ctla lien k�t, do
d6 lam cho lien l�t bSn vung h011.
106
Bai 54 - Thuy�t MO
Gia thi8t ion F; duqc t,;10 thanh tl't nguyen tll' F va ion p-.
a) Thuy8t lien k8t c(>ng h6a tri (thuy8t VB) c6 th� giai thich dm;rc s1,r htnh thanh ion F; theo con
dmmg neu tren hay khong? Giai thfch.
b) Ve gian d6 nang luQ'Tig MO va vi�t d.u h1nh electron phan tu cho ion F;. Theo thuy�t MO,
ion nay c6 t6n t,;1i hay khong? Giai thich.
HU'(mgd�n
a) Khong giai thich duqc vi theo VB, mot lien k�t cong h6a tri duqc hlnh thrum n't s1,r (i) g6p
chung m6i ben le doc than: di8u nay khong dl;lt dm_yc do p- khong c6 electron doc than ho� (ii)
cho nh� c�p e: di8u nay cung khong d,;1t duqc do F cr chu kl 2 nen khong con AO tr6ng.
b) Gian d6 MO Clla F;:
F
,...
.,.,
;,.
8-7
]
"
.,...
J..
,,
,...
J..
•
,
A
Bae
. !ten ket N::: --::: - . Bae !ten ket khac O nen theo thuyet MO, 10n nay ton tai.
.
2
2
.
107
.
Bai 55 - Thuy�t MO
1) Ve cftu true Lewis ciia F3CIO, F2CI02+ va F4CIO- , cho bi�t S\l lai h6a ci1a nguyen tu trung
tam.
2) Hay xay d1,rng gian d6 MO cho No- , va cho bi�t khi k�t hqp v&i H+ d� t�o than.h phan tu
HNO th1 luc nay H+ se lien k�t v&i N hay 0. Thir d1,r doan d�ng hln.h hc;>c ciia phan tir nay
Hll'mtg d§n
1) C�u true va d�g lai h6a cua nguyen tir trung tam:
F
0
lo
F-CI�
I�
sp3
sp3 d
2) Gian d6 MO ciia No-
11
1l
cr..,
ll
2r
Lr
. 1.1'
Khi tuong tac v&i H + thi mtrc tuong tac la orbital bi chi�m c6 mire nang luqng
cao nh§t (HOMO), a day chinh la lllllC n* v6n di c6 nang hrqng r§t g�n v&i N.
Nhu v{iy m{it do e tren N luc nay se cao hO'n so v&i O nen H + m1 tien gful vao
phfa N. Do H+ hie nay ttrO'ng tac v&i MO n* nen c6 th� d1,r doan r�ng phan tir
HNO se c6 d�mg g6c (Hinh ve).
108
H
Bai 56 - Thuy�t MO
S1,.t t6n t�i cua phan tll' NF da dttQ'C xac thlJC.
a) Xay dl,Tilg gian d6 mire nang lttQ'llg orbital phan tfr ciia NF.
b) Xac dinh b�c Lien k8t cua NF.
Hmrng d�n
a) Dmn day la gian d6 MO ctia NF. Do chenh l�ch v� th� nang orbital h6a t:ri gifta orbital 2s cfia
N (-25.56 eV) va 2p cua F (-18.65 eV) la 6.91 eV nen orbital cr2p dttQ'c d\t doan la c6 nan g luQ'llg
cao h011 so v&i nh6m 1t2p suy bi�n.
''
'
''
\�
H -o ...f
F
f
b) NF la ti�u phan ding di�n tu v&i 02. Do d6, NF dttQ'c d\t doan la c6 tinh thui;in tfr v&i b�c lien
k�t b§_ng 2. S6 lttQ'llg electron lien k�t (8 e) va phan lien k�t (4 e) trong gian d6 orbital phan tfr
ciing cho th�y c6 S\t t6n t,;1i Clla lien kM doi.
109
Bai 57 - Thuy�t MO
1) Pha.n ung c1.ia KrF2 v&i AsFs & nhi�t dQ gifta -78 d�n -53°C t�o thanh [K.rF][AsF6], m9t hQ'p
ch§t trong d6 KrF+ tuong tac m�nh v&i AsF6- qua du fluo1i.ne (nlm 1:rong hinh). D\t doan b�c
lien k�t Kr-F trong Krp+ se ngfu1 hay dai hO'n trong KrF2? Giai thfch ng�n gQn. (xem J. F.
Lehmann, D. A. Dixon, G. J. Schrobilgen, Inorg. Chem., 2 001 , 40, 3002.)
2) M�c du KrF+ va XeF+ da duc;rc nghien cuu nlnmg KrBr + thi clma di�u ch� duc;rc. V&i KrBr+,
hay: a) D� xu:lt gian d6 orbital phan tft; b) HOMO bi phan ewe v� phia nguyen ti'r nao? c) D\t
doan b�c lien k�t.
110
HU'(mgdiin
1) Mo ta vB orbital phan tu ca K.rF+ c6 th� dua ra d\f doan 1ing ion nay c6 cung s6 electron h6a
tti nlnr F2, phan tir c6 mot lien k�t d0'11. KrF2 ciing dm;rc d\f doan, tren cey s& thuy�t VSEPR, la c6
cac lien kM dO'll Kr-F, ngoai ra con c6 3 c�p electron clnra lien k�t tren Kr. S\f xuftt hi�n Clla cac
c�p clnra lien k�t trong KrF2 c6 th� lam cho d() dai lien k�t trong hqp chftt nay dai ra. Bao cao
th\rc nghi�m cho thfty d9 dai lien k�t Kr-F trong Ki·F+ la 176.5-178.3 pm; KrF2 la 186.8-188.9
pm.
2) a)
0
.·
o'
H ..Kr
>-4s
Br
b) HOMO phan C\fC vB phia Br do nang lm;rng cua 116 gfrn v&i orbital 4p cua Br.
c) B� lien k8t b�ng I.
111
Bai 58 - Thuy�t MO
a) Nlur da biBt orbital phan tir H2 + duqc bi8u di�n b�ng t6 hqp ruyBn tinh cac orbital nguyen tir
(LCAO). Cac orbital phan tir la
rA cr..1sA +ls 8
V&i lsA la AO th� hi�n tr:;i.ng thai ca ban cua nguyen tir hydrogen A va lss d6i v&i nguyen tir
hydrngen B. Nang lm;mg cua cac orbital phan tfr duqc chi ra & Hinh 1 du&i d,;tng mot ham cua
khoang each I ien nhan trong phan tu H2+. (Chu y 1ing thB nang gitra mot electron va proton duqc
cho la O (zero), urc electron va proton hoan toan Hieb bi�t). Cho bi�t dm'mg cong nang luQ'Ilg nao
cua cpl].
Energy/ eV
(2)
Internuclear distance/ nm
---.
0 1-1-r""lff"'l'"'l"'l""l""T-+-r-"l'"l""l""l""T.,..,..ff'l"..,..,..��-r◄
f1
Hlnh 1
b) Xac dinh khoang each lien nhan ci1a ti8u phan ben H2+.
c) Hai dm'mg cong nang lm;mg & Hlnh 1 se giao nhau & E1 cfmg lah'.lc khoang each lien nhan tr&
nen vo h:;i..n. Xac dinh thong s6 v�t ly nao cua nguyen tu hydrogen l!Ilg v&i muc nang luc:mg
IE1I.
112
HU'(mgdiin
a) Dm'.mg cong tren (2) & hlnh 1 chi ra nang lm;mg cua orbital phan lien k8t ( /Ja la mot ham cua
khoang each lien nhan.
b) Duong cong du&i fJ hlnhl chi ra nang luQ'ng ciia orbital lien k8t, <A . 1\'r qrc ti�u duO'ng cong
nang luQ'Ilg ta c6 the tinh dm;rc khoang each lien nhan ciia H2+ vao khoang 0.085 nm.
c) Hai duong cong nang htQ'Ilg tren hlnh 1 se giao nhau & E1 la diem khoang each lien nhan tr&
nen vo cung. Nhu vay H2+ da hoan toan ta.ch ra mot nguyen tit hydro va mot proton. Nhu vay
IE1 I cfmg chinh la nang luQ'Ilg ion h6a cua nguyen tit hydro.
113
Bai 59 - Thuy�t MO
a) Xa.c cqnh bi;ic lien k�t, thu t1,r tang dful chi�u dai lien k�t va tfnh ch§t tir ctia cac ti�u phan 02,
02+, 02,- 022- b) ViSt cfiu hlnh electron cua NF, NF, NP- theo thuySt orbital phan LU. Xac dinh s6 electron
clnraghep c�p va d1,r doan tinh ch§t n'r cua cac ti�u phan nay
Lttu y: C6 mQt s6 each kf hi�u cac orbital phan tit khac nhau, do tai li�u nay sir d\lng nhi�u
ngu6n tham khao khac nhau ncn chung toi gifr nguyen each ki hi�u rieng tit' m6i ngu6n.
114
HU'(mgdiin
a)
,'l l,...JL.:,----(
\_J_. .L�
\ � /
"""er
•,
'
�· ....
...
. JL/
!1-
.... -!t
0:,
O:'-
·-,,­
0
>-----ip
.-·•'
·,
!J-•
0
0,
0
Ti�u phan
o2+
02
o-
022
B�c lien k�t
2.5
2
1.5
1
Chj�u dai lien k�t
o2 < 02 <
o� < o;-
Tfoh chftt n'r
Thu� Thu� Thu{in
+
b) NF, Np+ va NF cung tuO'ng nr nlm 02, 02 + , 02·.
115
2
Nghj.ch
Ti�u
phan
Cau h1nh electron
NF
KK(la-) (2a/(3a°) (ln/ (27r )
NF+
KK(la°) (2a/(3a/(l 7r) (27r)
NF·
KK(la°) (2a/(3a°) (1Jr) (2n')
B�c
k8t
& tn;mg thai CO' ban
1
2
2
sa electron clnra ghep Tfnh cb�t
c�p
tu
2
2
2
Thu� n'r
4
1
2.5
l
Thu� tt'r
4
3
1.5
2
2
lien
116
Thu�n tt'r
Bai 60 - Thuy�t MO
Thuy�t orbital phan tit c6 th� ap d\mg d� xac dinh s1,r chi�m giu orbital cila CN, NN va NO.
a) Xac dinh b�c Lien k�t cila cac phan tit nay.
b) Phan tit na.o c6 nang ltrqng ion hoa (IE) 16n nh�t va nh6 nh�t? [IE(X) = .1H 0 r(X+) - .6H 0 r(X)]
c) Chftt nao c6 ai l\tc electron Ion nh§t? (PJ l\tc electron la nang luQ'llg giai ph6ng khl m9t ti�u
phan nh� them 1 electron, va mang d§u + n�u S\l nh�n electron toa nhi�t.)
d) Sl.l nh�n them ho� b&t cac electron tt'r CN ho�c NO t:;io thanh cac ti�u phan d�ng di�n tfr
(cung s6 electron) v&i N2. Cac ti�u phan d�ng di�n tit nay c6 lien k�t b@n hem hay kem b@n
hem N2? Giai thfch.
117
HU'(mgd�n
a) Xay d\rng cac gian d6 MO
o"
IJ
C
<:,,,,_._ fr
...;�
ipi .2,r,1,li>•
. "'· ..
J.#aj1i
....
-- .>
I I�a .. �·,·,·• ·., ��
� . ._.,.,
ip,.ip,-�.
J 0__,
--- •.•. •. •.•. •. .·. - �� I� 9"o··••••'·
•• - •••• ,
tc---
2.,
1.,
Is
N
N
0
Cac gian d6 nay bo qua S\t khac bi�t v8 muc nang hrQ'llg gifra cac nguyen tll' khac nhau, nlnmg
V�Ll cung dip cac lm&ng chinh xac, v8 m�t dinh tinh, d8 xac dinh b�c lien kk
118
Trong ca 3 trucmg hqp, cac orbital phan tir t:;i.o thanh tfr AO-ls, 2s d�u da dm;rc l§p d:ly nen
khong fmh lnr&ng d�n b�c lien k�t. B�c lien kM dm;rc xa.c dinh b&i khac bi�t trong S\f chi�m giu
cac orbital lien k�t va phan lien k�t t:;i.o thanh tfr AO-2p.
CN c6 5 electron trong cac orbital lien k�t s, p t:;10 thanh tt'r cac AO-2p va khong c6 electron nao
trong cac orbital phan Lien k�t. Do v�y b�c Lien k�t b�ng 2.5.
N2 c6 6 electron trong cac orbital lien k�t, b�c lien k�t b�ng 3.
NO c6 6 electron trong cac orbital Lien k�t va I electron trong cac orbital phan lien k8t - chenh
l�h 5 electron, do v�y b�c lien k�t la 2.5.
b) 0 day, chung ta dn chu y d�n cfi.u hlnh electron t:;i.o thanh nr S\t m�t electron.
D6i v&i CN+, du h1nh electron mm la
C
N
D6i v&i N2 +, electron bi tach ra thuoc orbital lien k�t p dta N2, trong ldri d6, v&i NO+ la electron
cu.a orbital phan lien k8t p* cua NO. S\t tach electron phan lien k8t se lam b�n hoa NO+, do v�y
NO se c6 nang luQ'l1g ion hoa th§p nhit (d� tach electron nhit.)
S\t ion hoa CN hay N2 doi h6i phai tach electron tlt mot c�p electron ghep doi trong orbital lien
k8t, do v�y IE(CN) va IE(N2) kha g§n nhau. Chung ta d\1' doan r�ng IE(N2) se l&n hon IE(CN)
mot chut, do S\t xen ph11 gifra cac AO ctia hai nguyen tir N se t6t hon ctia cac AO ctia C va N. Do
v�y: IE(NO) < IE(CN) < IE(N2).
Cac gia tri nay duo-c xac dinh trong th\rc t� la IE(CN) = 1359 kJ mol-1; IE(N2) = 1503 kJ mol-1;
IE(NO) = 894 kJ mol-1) - xac nh� nhung l�p lu�n tren la c6 ca s&. Chu y 1ing IE(NO) th§.p h<.111
so nhi�u so v&i hai gia t1i con I:;i.i, cho thiy r�ng vi�c Hieb electron kh6i orbital phan. lien k�t d�
h<.111 so v&i orbital lien k�t
c) N2· va No- duQ'c t:;i.o thanh b&i s,r cong them 1 electron vao orbital phan Lien k�t. NguQ'c l:;ti,
CN- duQ'c t:;i.o thanh b&i cong electron vao orbital lien k8t p (t:;i.o thanh ti�u phan dfutg di�n t1,1' c6
c§.u hlnh electron gi6ng N2.)
119
Do v�y, ta dv doan CN c6 ai Ive electron (EA) Ion nh§t (d� cong them electron nh§t.)
Cac gia tri thvc t� la: EA(CN) = 369 kJ moi- I; EA(N2) - 0 kJ moi- I; EA(NO) - 9 kJ mo1- 1.
d) Nh1n ch ung, s1,r xen phu se la mi;mh nh§.t n�u xay ra giua cac AO cu.a nguyen tfr gi6ng nhau, do
v�y tu c6 th� d\! doan N2 c6 lien k�t b�n nhfit. Tuy nhien, s1,r so sanh nay phtrc t:;tp hon th� b&i
NO + va CN- la nhfrng ti�u phan mang di�n; qua tr1nh phan Ii lien k�t cua chung la
cN---+- C- + N (do ai Ive electron cu.a C > N)
N2--+- N + N
NO +--+- N + o+ (do nang hrqng ion hoa cu.a O < N)
S\! t�o thanh lien k�t c6 xu lnr&ng 6n d:inh di�n tfch, bfit k� la di�n tich am hay du011g, do v�y k�
ca khi s1,r xen phi1 trong N2 la tat h011 thi cilng kh6ng hin N2 da c6 lien k�t b�n nh§t trong s6 3
ti�u phan d�ng di�n tir. N�u khong c6 them thong tin th'i cau hoi nay khong tra 16'i C\l th� duqc.
(Cac du li�u thl,!C t� ghi nh�n dtrQ'C la: D[(C-Nt] = 994 kJ mo1- 1; D(N-N) = 946 kJ mo1- 1; va
D[(N-O/] = .1051 kJ moi- 1• C6 th� thfiy rfulg trong ca hai tnr6'ng hqp th'i s1,t 6n dinh di�n tich d� u
vuqt trQi hon s1,r xen phir trong N2.)
120
Bai I 00 - Thuy�t MO
Hay ve gian d6 MO cua 02 trong hai phuc chiit ciia coban. Bi�t rfu1g
Do dai lien k�t O - 0 (pm)
Chiit
Momen tu (µB)
[Co2(NH3) 10]02]4+ 147
[Co2(NH3) 1002]5+
130
02
121
H2O2
147
0
1,71
Hmrngd§n
O\ra vao momen tt'r c6 th� bi�t trong [Co2(NH3)10O2] 5+ c6 le doc than, do dai lien k�t n�m gitra
02 va oi 2- nen ph6i ti'r 02 trong phirc phai la Of. Con ph6i tu 0i trong [Co2(NH3)1o]O2] 4+ c6
momen tu b�ng Ova d(> dai lien k�t O - 0 gi6ng H2O2 nen 116 se & cl:;ing 0z 2-. Nim v�y gian d6
MO cua Of va oi 2- nlnr sau:
01-
**
*
;*
*
02
crX*
..
ny,z
n y,z
v'x
cr*
s
0"5
*t
***
*
*
GX *
TCy ,z *
TCy,z
Gx
Gs*
Gs
121
Bai 61 - Cfiu hinh electron va tinh ch§t tw
2
Cfiu hlnh electron Clla phan tit H2 & 1:r:;tng thai eo ban la ( crls ) . Cho cac tr:;tng thai kfch thfch:
(a)
t -!.- ; (b) t t ; (c)
ti
Hay so sanh mite nang lm;mg ci1a cac tr:;lng thai nay. Tr:;ing thai kfch thfch c6 mite nang lm;rng
thfip nh§.t c6 tinh thu�n tfr hay nghich tfr?
Hm'.Yngd§n
Do ca 2 electron Clla (c) d�u thU<)C orbital phan lien ket nen so v&i tr:;ing thai C(Y ban, Ee c6 mt'tc
nang lm;rng l&n hon (2p). Trong khi d6 v6i (a) va (b) thi cac electron d8u thu(k ca orbital Lien ket
va phan lien ket. Trang (a) thl spin ciia 2 electron nguqc nhau, con (b) c6 2 electron cung spin
nen nang luqng cfia tr:;ing thai (a) 1611 hon (b) mot chut.
Tr:;ing thai c6 muc nang luong th§p nh§t (b) c6 tfoh thu�n tfr.
122
Bai 62 - B�c lien k�t
1) Hay so sanh b�c lien ket, d9 dai lien ket cua cac phan tfr d6ng ha.ch sau: B2, C2, N2, 02, F2.
2)
0 tra.ng thai co ban, C2 la phan ttr nghich tir. Hay viet d.u h1nh electron cua phan tfr nay. Cho
biet d9 dai lien ket trong phan tir C2 do dm;rc la 124 pm, gia tri nay ngfu1 hon d() dai Lien ket
doi tinh theo ban kinh c()ng h6a tri ctia carbon (2·67 pm).
+
3) Theo thuyet orbital phan ti'r thl lien ket trong Cb yeu hay m�1.11l1 hon Ch ? Ta.i sao?
Hmrng d§n
1)
2) C�u hlnh electron cua C2
( cr2s
r� ( • )2 ( )4
cr2s
7t2p
Do s1r chenh l�ch nang ltrQ'11g orbital s-p nen cr;, la orbital phan Lien ket yeu. Phan tfr C2 c6 b�c
lien ket nfun trong khoang 2 - 3. Chinb vl vl;iy, do dru lien kBt do dm;rc ngful hon so v&i do dai
lien kBt doi tinh theo ban kinh c()ng b6a tri.
3) Lien kBt trong Ch yBu hon trong Cb+.
0 tra.ng thai co ban, c�u hlnh electron cua Ch la
( 0'3J 2 ( O';s f (0'3 ,,, )2 (n3 " )4 (n;,, )4
tuong rrng v&:i b�c lien kBt b�ng 1. Trong khi d6 Cb+ c6 it hon 1 electron a orbital phan lien kBt,
nen bl;ic lien kBt la 1 .5.
123
Bai 64 - B�c lien k�t
Ve gian d6 orbital phan tu va vi�t c§.u h1nh electron tr�.ng thai C(j ban Cll.a cN-. T.fnh b?C Lien k�t
va moment tt'r (bo qua a.nh lnr&ng Clla S\t chuy�n dong orbital vao moment tt'r).
HU'(mgd§n
cN- va N2 Ia cac ti�u phan "d�.ng di�n ti't". Gian d6 orbital phan tir cua cN- va N2 g§J1 nlnr tu<:1ng
d6ng. Cau h1nh electron & tr�ng thai ca ban la:
2
4
(Iaf (2o-) (I1r) (3o-}
2
(cung c6 th� vi�t la: (cr2,) 2 (cr;J 2 (cr 2P) 2 (1t2P ) 4 )
B�c lien k�t;;;;; 3.
S6 electron kh6ng ghep c�p b�ng 0, do d6 moment tt'r b�g 0.
124
Bai 65 - B�c lien k�t
Ve gian d6 orbital phan tfr, tfnh b�c lien k�t va moment tt'r cua NO. So sanh dQ b�n va.dQ dai lien
k�t NO va NO+.
HU'(mgd§n
Gian d6 orbital phan tfr cfia NO
B�c lien k8t
1
= - (8 - 3) = 2.5
2
S6 elet:ron chua ghep c�p bkg 1, gia tri moment tl'r la
✓
µ = 1(1 + 2)/Je = 1.73/Je
Do NO m�t l electron phan lien k�t 2nd� t<;10 thanh NO+ nen b�c lien kM la 3, do do lien k�t h6a
hQc cua NO+ b�n hon NO. H� qua lad(, dai lien k8t cua NO+ ngful hO'll NO.
125
Bai 66 - B�c lien k�t
Nang hrQ'ng lien k�t Clla CF va CF + la 548 va 753 kJ moi- 1 (clma biSt gia tri nao tmg v&i ti�u
phan nao). Sir d\mg thuySt orbital phan tu, hay gan cac gia tri na11g luQ'ng Uen kSt v&i ti�u phan
tuong ung.
Hmmgd�n
C§.u hin.h electron cua CF & tr�ng thai cO' ban la:
Bae lien k�t
.!.(8-3)::: 2.5
2
CF+ co it hem CF 1 electron b:en orbital phan lien kSt:, nen 116 co b�c lien kSt b�.ng 3. Do do lien
kSt CF + se b�n hc:1n CF. V�y nang luQ'ng lien k81: cua CF va CP bin luQ't la 548 va 753 kJ mo1- 1•
126
Bai 67 - B�c lien k�t
V6'i cac phan tir d�ng AB nao sau day: N2, NO, 02, C2, F2, CN, CO, XeF, thi ion fun hrO'ng 1'.rng
AB- c6 nang lm;mg lien k�t Ion hon d�ng trung hoa? Ion drrong hrO'ng rrng AB+ nao c6 nang
luQ'11g lien k�t 16'n hon d�ng trung hoa?
Hmrngd�n
N�u electron dm;rc di�n them vao orbital Lien k�t thi nang hrqng lien k�t ci1a AB-> AB, con n�u
electl:on di6n vao orbital phan lien k�t thi nang hrQ'l1g lien k�t cua AB-< AB. Trong tiuang hqp
t�o thanh cation (m�t electron), n�u electron bi m�t tu orbital phan Iien k�t thi nang lrrqng Lien
k�t AB+ > AB, con n�u electron m� tu orbital Lien k� t thi nang luQ'l1g lien k�t AB+ < AB. Tren cCI
, k;..et lu:;m
� sau:
SCI
• nay,
' co, th"e rut
, ra cac
Sau khi nh�n them electron chuy�n thanh AB-, C2 va CN c6 nang lm;mg Lien k�t 16'n hem phan ur
tnmg hoa. Sau khi mM electron d� tr& thanb AB+, NO, 02 , F2 va XeF c6 nang luQ'llg lien k�t 16'n
hO'n phan nr 111mg hoa. Trong trm'rng hqp N2 va CO, s\r nh�n electron d� t:;io tbanb ion am (N2-,
co-) va m�t electi·on d� tr& thanh ion duoog (N2+, co+) d�u lam giam nang luQ'llg lien kk
127
12 8
Bai 68 - Thuy�t MO
Sir d1,111g He (21.22 eV) lam ngu6n kich thich, xac dinh dong nang quang di�n tu nh�n duqc b6'i
s1,r kfch thfch electron ciia 3 orbital phan tir trong N2. Dm:n day la ph6 quang di�n ti'.r cua N2 v&i
cac orbital phan tu tuo11g frng ci1a m6i dai ciing duqc cho trong h}nh.
2o,
I 1t.
'
16
l..
18
lo.
..
Ut.V
20
40
Ph6 quang di�n tir cua N2
Hlf6'ng d�n
Theo u&c tfnh tt\' ph6 quang di�n nr, nang luqng ion h6a ct\a cac orbital phan tir ciia N2 6' trc;1ng
thai C<:J ban la: lcrg: ~40 eV; lcr u : ~10.80 eV; lnu : ~16.70 eV; 2crg: ~15.60 eV. Nang luqng Clla
ngu6n He chi c6 th� ion h6a lcr u, lnu, 2crg.
V&i cac m§u khf, cong thoat Ctla chinh may do ph6 duqc bo qua. Dong nang cila cac quang di�n
tu c6 th� t:fnh b&i cong th(rc sau:
Trong d6 Ette, Eb, IA lfu1 hrqt la. nang lm;rng Clla ngu6n kfch thfch, nang hrqng lien k�t electron, va
nang luQ'llg ion h6a ct\a orbital. Dua cac gia. tri phu hqp vao, se thu duqc cac gia t:ri dong nang
quang di�n nh{ln duqc b&i s1,r kfch thfch electron cua cac orbital lcr u , lnu ,2crg trong phan tfr N2:
21.22eV -18.80eV::: 2.42eV
21.22eV -16.70eV::: 4.52eV
21.22eV -15.60eV::: 5.62eV
129
Bai 69 - Nang lm;mg ion h6a phan tir
Tfr die thf nghi�m ph6 quru1g di�n tfr nr ngo:;ii thfty rfu1g nang ltrQ'llg ion h6a thu nhftt cirn phan tu
NO (9.26 eV) thftp h011 kha nhi�u so v&i CO (14.01 eV). Hay giai thfch, d\ra vao du hlnh
electron cua phan tfr.
Hmrngd�n
C§.u hlnh electron ciia phan nr CO:
C�u hlnh electron Clla phan nr NO:
2
4
2
(laf (2a') (ln) (3a-) (2n)'
Nang lm,rng ion h6a thu nhftt cua phan tu CO la nang luqng t6i thi�u c§n d� lo� electrnn 3cr.
Nang hrqng ion h6a thu nh�t cirn phan tu NO la nang hrqng t6i thi�u dn d� lo� electron 2n.
Electron 3cr la cac electl'on lien k�t v&i nang hrQ'llg th�p h011, do d6 nang hrqng ion h6a thu nh§t
cua NO nho hon nhi�u so v&i CO.
130
Hoa ltr(fllg tu
Bai 70 - H(>p th� m(>t chi�u
Trong ca hoc lm;mg tl'.r, mo hinh h� t trong hop th� mot chi�u mo ta mot ti�u phan di chuy�n giua
hai buc tu&ng kJ1ong th� vu<;Yt qua dUQ'C each nhau mot kJ1oang each L. Muc nang luqng dUQ'C
phep cu.a mot ti�u phan 1l:ong hop th� mot chi�u cho boo bi�u tln'.rc:
n 2h2
En= --2
8mL
v&i n = 1, 2, 3, ....
V &i h la hrtng s6 Plank, m la khdi lm;mg rut gc;m ci1a ti�u phan va L la ch.i8u dai hop tht
Ph$ h§p tlm di�n tir cu.a mot phan tu thfulg lien hq p c6 th� duqc mo ta brtng mo hlnh hop th� mot
chi�u. Cac electron n b�t dinh xu duqc xem nlur cac electron ti,r do va chung duqc phan b6 tren
cac ml'.rc nang luqng duqc phep du&i s1,r di�u khi�n ci'1a nguyen ly lo�i tn'r Pauli. N�u phan tir
chl'.ra N electron n b§t dinh xl'.r thl muc nang luQ'1lg tu n = 1 d8n n = N/2 goi la tr,;111g tl1ai ca ban.
Hinh du&i chi ra cac ml'.rc nang luqng cho cac phan tir thing lien hop c6 N = 8.
n=5
l
Cac muc nang luqng trong h� c6 8 electron t1,r do, N=8
Bu&c chuy�n nang luO'Dg th§p nh�t trong h� chinh la bu&c chuy�n mot elec tron u'r tr,;lllg tl1ai ca
ban n = 4 (N/2) len tr,;1ng thai kfch thich n = 5 (N/2 + 1). D� bu&c chuy�n nay c6 th� xay ra khi
h§p th1,1 anh ang thi bu&c s6ng anh sang t&i phai thoa man.
�E = 11.C
,i, '
�E = � [(� + 1)2 - (� )2]= �2 (N +I)
Bml.2
2
2
8mL
Cyanine, pinacyanol, va dicarbocyanine (cfiu trl'.1c cho du&i) la cac phan ttr phfun nhuom c6 c§u.
true m�.ch lien hQ'p gitra hai d�u m�h.
131
cy anine
pinacyanol
H3C e
,
H3C/
••
CH3
N=C+-c=c+N/
H
H
H 3 '-...CH
3
dicarbocy an ine
a) Ve die c§u true c9ng lnr&ng cu.a m6i phan nr.
b) Cac electron b§t dinh xl'r c6 th� di chuy�n t1,t do trong vung giua hai nguyen tir nitrogen d�u
m:;ich nlnmg kh6ng di chuy�n d�n cac lien k�t nfun ngoai nguyen tit nitrogen. Mo hlnh h9p
th� m9t chi�u c6 th� duQ'c ap dw1g d� tinh na11g luQ':ng hrQ'Tlg nr h6a cu.a cac electron b§t dinb
xir. 09 dai h9p th� c6 th� dUQ'C cho la khoang each giua hai nguyen tit nitrogen, dUQ'C xac
dinh dQc theo cac lien k�t carbon-carbon cung v&i m6i lien k�t C-N. Xa.c dinb s6 electron b§t
dinh xl'r N trong m6i pban tit ph§:m nhuc)m.
c) Th1,tc nghi�m cho thfty dai h§p thµ ci,rc d� cfra ba ph§:m nhu9m cyanine, pinacyanol, va
dicarbocyanine lfu1 luQ't irng vcri cac bu&c s6ng Amax 525, 605 va 705 nm. Ti:nh �E cho
cyanine, pinacyanol, va dicarbocyanine.
d) Xac di:nh quang dm'mg cac electron c6 th� di chuy�n t1,t do trong cac phan tfr nay.
e) Cac. electron n bftt dinh x ir c6 th� di chuy�n t\t do trong polyene nlnnig khong th� vuQ't ra
ngoai nguyen tfr, vl th� chung c6 th� xem nlnr mo hinh hop th� mc)t chi�u duQ'c xac dinh b&i
be) khung carbon trong polyene th�ng. De) dai t:rung blnh cfra lien k�t carbon-carbon trong cftu
true lien hQ'p la 140 pm. 89 dai cfra m:;ich carbon, tl'.rc chi�u dai h9p th� xftp xi L= 2jx140 pm,
v&i j la s6 cac lien kM doi trong polyene. Xac dinb sd electron bit dinh xl'r va de) dai m:;ich
lien hQ'p L trong 1,3-butadiene va 1,3,5-hexatriene.
f) U&c luQ'ng t:§n s6 va bu&c s6ng cfra bu&c chuy�n di�n tfr c6 mire :na:ng htQ'ng thip nh§t trong
1,3-butadiene va I ,3,5-bexatriene.
132
HU'(mgdiin
a)
../
©/
-N
.,.____.,. "'-··
N-c=c-c=N
"'.@
N=c-c=c
/
H
H
H
'---.
/
H
H
H
'---.
b) Ne la s6 nguyen tit carbon c16ng g6p 1 electrnn, NN+ la s6 nguyen tfr nitrogen c16ng g6p 1
electron, NN la s6 nguyen tir N c16ng g6p 2 electron.
N = lx Ne+ lxNN+ + 2xNN
Cyanine: N = 6
Pinacyanol: N = 8
Dicarbocyanine: N = 10
c)
Cyanlne
9
h
llE = e = 6.6261 10 k x2.9979 10 = 3_78. 10.,. J
Pinacyanol
O.E =
Dlcarbocyanlne
ti
525-10-9
he= 6.6261 · 10 J-4 x2.9979 10
�
605 ·10 ,II
·
9 = 3 28 _ 10 ,a J
/lE =he= 6.6261 10·34 x2.9979 ·106
�
705 ·10 "°
= 2_82. 10.10 J
d)
m0 9.10 94><10-31 kg
=
Cyanine:
L = 5.507 ·10·1 x (6+ 1) >< 525 1 0)H = 1056pm
Pmacyanol·
L=5.507 10 7 x{(8+1)x605·10 )
Dlcarbocyanlne:
L =5.507 -10·7 x{(10+1)x705 -10·9)" = 1534 pm
(
o·
9
112
=1285pm
2
e) 1,3-butadiene: N = 4 x 1 = 4, L = 4 x 140 = 560 pm
133
1,3,5-hexatriene: N = 6 x 1 = 6, L = 6 x 139 = 840 pm
f)
tE =
(
h2
-8m L 2
)
(N +1) = 6.025 ><10
-�
N +1
>< -L2
'>D
N +1
19
1,3-butadiene: N = 4 and L = 560 pm, /£ = 6.025 • 1o-- >< -2- = 9.60 • 10- J,
L
),. = 206 nm
1,3,5-hexatrlene: N = 6 and L= 840 pm, 6E = 6.025 • 10
>. = 332 nm
134
-38
x
N +1
10
= 5.98 · 10 J,
�
Bai 71 - H9p th� m9t chi�u
a) Tinh bu&c s6ng cua mQt buc x� di�n tu dn d� kich thfch mQt electron tt'r tr�g thai ca ban
len muc nang lm;mg n = 5 trong mQt h(>p thS m(>t chi�u da:i 40.0 pm.
b) M(>t electron trong m(>t h(>p thS mot chi�u dn bu&c song 8080 mn d� kfch thfch tu tr�g thai
11 = 2 len 11 = 3. Tinh dQ da:i Cll.a h(>p thS nay.
c) M(>t electron trong h(>p thS m(>t chi�u 10.0 tun duqc kfch thfch tfr tr�ng thai cO' ban dSn m(>t
tr�ng thai cao hO'n b�ng each h�p th\l m(>t photon cua buc x� di�n tt'r c6 bu&c s6ng l.374xl025
m. Xac dinh tn,mg thai nang luqng cu6i ci1a bu&c chuy�n nay.
d) E)i�u g1 se xay ra v&i cac mire nang luqng cua mot electron bi giu trong mot hop thS mot
chi�u khi chi�u dai hQp thS tang len? D\t doan mire nang luqng & tr�ng thai CO' ban cua
electron trong mot hop thS mot chj�u do da.i 10 --6 m se thftp hay cao hO'n so v&i trong hop th�
10- 10 m?
135
HU'(mgdiin
a)
�E =
E
24(6.626 X 10-31 J <i) 2
(9. I 09X JO-JI kg)( 40.0 X 10 "12 m f�
he
l
).
9.04 X 10 16 J
= he = (6.626 x 10-\1 J ·)(2.998 x 108 m�
9.04 x l0-16 J
t\l:.
2_20 x 10 10m
0_220 nm
b)
he - (6.626 X 10-11 J )(2.998 X 108 m/\)
TC
2.46
080 x 10
10 20 J
9
2.46 X (Q ?OJ
m
1
5(6.626 X J 0-' J 5)
----- - --•
, 1
2
.,
l ml:
2
8(9.109X 10- kg)T
I..
3.50 x 10 9 m
3.50 nm
c)
( h
----
n2 h 2
l
8me
8ml2
(6.6261 10
he
-X
/\F
2
11 J
)(2.9979 X )()ij m/ ')
1.446 X IO 20 J
A
1.374 X lO-� rn
1.446 X 10 ?OJ
n\6.626 x w-" J ) 2
(9.109x 10-11 kg) (l0.0x 10-9 rnf
(6.626 X 10 '-' J ) 2
(9.l09x 10 11 kg) (L0.0x 10 9 m) 2
1.506 X 10 ?O
6.02 X 10 ?l
136
25.0. 11
5
n 2h
: , khi L tang len thi En se giam va khoang each gifra cac mtrc nang
8mL
hrong cfmg se giam. V�y nang hrQ'llg mt'.rc tn,mg thai ca ban cua electron trong hop th8 10-6 m se
thftp h011 so v&i hop thfl 10- 10 m.
d) Theo cong thl'.rc: En =
137
Bai 72 - Hoa hQc lmyng tir kha ki�n
Bu&c d§u ti.en trong co ch� dt phirc tc;1p c1ia S\t nhin b�ng m�t la s1,r d6ng pha:n h6a cis ➔ trans do
S\t quang cam l.'rng gay ra cho nh6m retinal mang mau bi khu§.t trong cac phan tit rodopxin (c6
trong v5ng m�c cu.a mit). Cis-retinal h§p th1,1 dm;rc anh sang nhtn thfty do thay d6i cfiu hinh cfia
mQt I ien k�t doi:
h
�
0
cis-retinal
trans-retinal
1) Hay chi ra Lien k�t doi da tham gia vao S\t d6ng phan h6a cis-trans. Hay xac dinh t9a dQ ctia
phan tmg.
2) mi fun thfiy r�ng nang lm;rng Clia cac ti�u phan tham gia va tc;lO thanh la mot ham tuful hoan
Clla tQa dQ phan tmg X:
Eci-l (x) = 1.79·(1-cos(x))
E ir.llisCx) = 1 .94+0.54-cos(x)
Dem vi nang ltrQ'llg la eV (1 eV = 1.60. 10- 19 J = 96500 kJ/mol), x = 0 (tuong) 1mg v&i chfit tham
gia phan 1'.rng; x = 1t ung v&i san phfun. Hay ve gian d6 nang lm;r:ng cho phan ung. Hay xac dinh
bi�n thien nang lmmg va nang hrqng hoc;1t h6a cu.a phan irng nay.
3) Do dai l&n nhfit cu.a s6ng ma cis-retinal c6 th� hfip thu b�g bao nhieu?
Ta hay ap d1,mg mo hinh "hc;1t trong hQp th�" cho electron c6 trong h� lien hqp cu.a cis-retinal.
Nang lm;rng mot hc;1t c6 kh6i lm;rng m chuy� n dQng trnng hop th� mQt chi�u v&i b� r9ng C duqc
(hn)
2
tm
1eu th'uc·. En = --, ; n = 1 , ?-, 3 , ... , nguyen.
/ h theo b·"
8mt·
4) C6 bao nhieu electron trong b� lien hqp d1a cis-retinal?
5) D1,ra vao cau tra lai cac cau hoi 3, 4 cila bc;lll va dung cong thfrc tren, hay tfnh C . Hay so sanb
tri s6 nay v&i cftu true ciia phan tu retinal.
138
HU'(mgdiin
1) Phan img xay ra khi quay m9t phfu1 ei1a phan tit quanh lien k�t C11-C12
I
G6e quay la to,;l d9 el\a phan img.
2)
Trans
·1
0
2
3
4
Reaction coordinate x, rad
Bi�n thien nang lm;mg eua phan ung la hi�u eae Cl,te tiBu nang lue,mg eua hai d6ng phan trnns va
c1s:
Q = E1rmu(1t)-Ecis(0) = 1.40-0 = 1.40 eV = 135 kJ/mol.
Trl;lllg thai ehuyfui ti�p eua phan img n�m Hin e:;in giao diBm eiia hai ducmg eong:
J.79 · ( L- eos(x)) = J.94+0.54· eos(x), x = 1.64 = 0.521 re= 93.7 °.
Nang luong ho�t dong hoa Clla phan ung due.re xac dinh b�ng hi�u gitra eae nang luong Clla tri;1ng
thai chuy@n ti�p va ch�t tham gia phan 1mg:
Hang rao nay hoi eao, n8u phai vuot qua & nhi�t do moi tnrong.
3) Do dai s6ng qre di;1i due.re xae dinh b�ng ehenh l�eh nang luong giua tr,:mg trhai trans va eis
eua S�C t6 vong ITI,;l.C tl;li X = 0:
139
19
he =E1r;ns (0)-Ec. (0) = 2 .48-0 = 2.48 eV = 3.97·10- J.
IS
/\,
11.= Ile
6.63·10-3�.J.OO·lOs
=
=5.0l·l0-1 m=501 nm.
t.E
3.97·10- 19
4) H� electrnn lien hqp cln'.ra 6 lien k�t doi, nrc la c6 12 electron chi�m 6 muc nang lm;rng th§p
nh§t
5) Khi h§p th\l anh sang se xay ra s\r chuy�n ti.'r muc nang lm;mg bi chi�m cao nh§t sang muc con
tr6ng th�p nh�t:
trong d6 kh6i lm;mg electron m = 9.11·10- 31 kg. Rut ra:
l=
J 311 2
= 6.63·10- 34
8mi1E
J3
8·9.11·10- ·3.97 ·1031
19
=l.4I·I0-9 m=l.41m.
Gia 1ri nay plu\ hqp t6t v&i t6ng cac de;, dai lien k�t trong h� lien hQ'p nay - 6 hen kM kep va 5 lien
k�tdan.
140
Bai 72 - H9p th� m9t chi�u
Cac polyene tnc;ich thing (--··-CH=CH-CH=CH-CH=CH-····)
la ph§n du true h6a hQC trong phan tu c6 kha nang h§.p th\l anh
sang kha ki�n. Xet cac electrnn n trong cac polyene m�h th�g
nay.
D�u ti.end� chodan gian chung ta se khao sat cac electron n cfrn
1,3-butadiene chira 4 nguyen tfr carbon b�ng plurong phap g�
dl1ng Huckel. Cho r�g mi�l ph�ng chl'.ra tnc;ich carbon n�m vuong
g6c v6'i trl)c z va orbital nguyen tfr 2pz cu.a m6i nguyen tfr carbon
dUQ'C gQi la </>; (i = 1, 2, 3, 4). Orbital phan nr lf/k dUQ'C bi8u di�n
z
Hlnh I : Mo ta du true h6a hQC
ciia 1,3-butadiene. M6i nguyen tfr
carbon d�u da. dtrQ'C da.nh s6.
du&i dc;ing t6 hqp tuy�n tfnh cac orbital nguyen tfr d\ra vao plmong trinh sau:
Tich phan CoulombdUQ'C ky hi�u a. va tfch phan c(>ng hm:mg gifra cac nguyen tu k� C�ll lap, v6'i
p la nang luQ'Og cu.a orbital 2pz ct1a m6i nguyen tfr carbon tach bi�t vap c6 th� coi la SlJ xen phu
gifra cac orbital 2pz k� c�n. Tri nang lu<;Yng Ek va cac orbital phan tfr tuong irng c6 th8 thudUQ'C
b�ng nhiBu phuang phap khac nhaud8 thudUQ'C:
& 1 = a -1.62/3
lf/1 = 0.37 </>1 -0.60¢2 + 0.60¢>3 -0.37 </>4
(2)
&2 = a -0.62/3
lf/2
= 0.60¢1 -0.37 </>2 -0.37 </>3 + 0.60¢>4
(3)
&3 = a+ 0.62/3
lf/3 = 0.60¢1 + 0.37 </>2 - 0.37 ¢3 - 0.60¢4
(4)
&4 = a + 1.6 2/3
l{/4
= 0.37¢1 + 0.60¢2 + 0.60¢3 + 0.37 ¢4
(5)
a) Ve cac orbital phan tfr theo mire nang hrQ'ng, chi ra cac
electron 1t a tr:;mg thai CO' b�ng bkg each SU' d\mg cac mfu ten
va c6 hm yd�n chi�u spin.
b) Sfr d\mg a. va P, tinh toan nang lu<;Yng c�n thiM d8 photon c6
th8 kfch thfch phan tfr 1,3-butadiene n'r tr�mg thai ca ban !en
trc;lng thai kfch thich thl'.r nhk
Hinh 2: Mo ta cac orbital
c) Ve orbital bi chi�m c6 mt'.rc nang lu<;Yng cao nh§.t (HOMO) va phan llr 1t ct'ia ethylene.
orbital khong bi chi�m c6 muc nang lu<;Yng th§ .p nh§t (LUMO) M6i vong b·on d�m net
bi�u di�n m◊t nut
cua phan tir 1,3 -butadiene d1Ja tren vi d\l v� phan tlt etylen &
Hlnh 2, trrc la hay ve 4 orbital 2pz vuong g6c v&i. tn,1c ngang
r6i chi ra d�u cua m6i orbital b�ng cac mau den va t:dng. TiSp nfia hay biSu di8n cac nut
b�ng cac vong trond�n net Khong cfln thi�t phai bi�t m6i ph§ndong g6p cua orbital 2pz vao
orbital phan tfr.
141
Ti�p theo hay xet cac electron n trong nhtrng h� th6ng c6 s6 nguyen tir carbon dh l&n ch�ng h�n
polyacetylene. Ap d\mg mo hlnh h{)p thB m{)t chi�u d6i v&i rn{)t s6 lm;mg xac di.nh (N) cua cac
orbital 2pi:. dinh lm&ng th�g g6c v&i m:;1.ch phan tit v&i khoang each a. N�u chimg ta dl;lt mQt gi&i
h:;i.n I� l�i (pe1iodicity boundary) la Na d9c theo m �ch thl tr�ng thai nang lm;mg ci1a cac electron
n c6 th� dm;rc mo ta. boo plmong hinh sau day:
Ek ::: a.+ 2J3 cos ka
7t 7t)
21tp
k:::-,p=0,±1,±2,... --�k<Na
a
( a
(6)
d) Tinh s,r chenh l�ch nang lm;mg gitra ml'.rc qrc d:;1.i va qrc ti�u cirn electron n.
e) Do khoang each nang lm;mg trong m�ch n;ra h{)p th8 mQt chi8u rftt nho nen cac mt'.rc nang
lm;rng c6 th� t:;1.0 thanh cac tr�ng thai lien tl,lC. Nlm vay S\I kfch thich nhi�t u'r HOMO len
LUMO r§t d� dang & nhi�t d{) phong. Ml;lc du
(a) t>crlodlcily: a
cac electron kfch thfoh nhi�t luon chuy8n d{)ng
(I
+----7
trong m:;i.ch va dong g6p vao tinh d§n di�n
nlumg polyacetylene ti.uh khiBt la ch§t d§n
·-· �a� � � � � � � --���o
di�n kem. Di�u nay do cac nguyen tu carbon
trong polyacetylene kh6ng dm;rc s�p x@p v&i
---- �-�
� � � �� �
do l�p l:;i.i a; ma thay vao d6 cluing dm;rc s�p
·-;��o
x@p v&i do l�p l:;i.i la 2a do S\I s�p x@p luan
(b) r�riudicily: 20
E 2a
phjen giua cac lien k@t dan va doi. N@u
J
HOMO va LUMO cua 111:;i.cb n;ra hop th@ m{)t
chi8u c6 d9 l�p l:;i.i la a va 2a duqc bi�u di@n
nlm & Hlnh. 3(a) va (b), tb:l ml'.rc nang ltrQ'llg
ciia HOMO va LUMO se bi anh lur&ng nlur
th@ nao n@u do Hip l�i chuy�n tu a thanh 2a?
Ch9n can tra Im dtmg u·ong s6 cac y sau day:
A. Do b�n cirn HOMO giam trong khl LUMO
tang.
B. Do b�n cua HOMO tang trong khi LUMO
giam.
Hinh 3 : Mo ta. LUMO va HOMO cim m�ch
n.ra hQp th� mQt chi�u v&i dQ l�p !:_ti a (h1nh
tren) va 2c, (hinh dtr&i).
D
C. Ca HOMO lful LUMO d�u duqc b�n h6a.
D. Ca HOMO lful LUMO d�u giam b�n.
Coad,_.,..,
Valence band
f) M�ch n;ra hop th8 mot chi8u c6 do l�p 1:;i.i 2a cho
th§.y mot kboang tr6ng gitra cac tr�ng tbai lien t\lC,
di8u nay d§n d�n S\I t:;1.0 thanh mot vung h6a tri
chl'.ra electron va vung d§n clma ch§.t dfiy nlm dm;rc
mo ta & htnh. 4. Do vung h6a tri da. di8n dfty
electron va khong c6 mot trang thai chua bi chi�m
142
Periodicity : la
H1nh. 4 : Mo ta cac tnµ1g thai di�n tir lien
cim m,:1Ch tl_ta hQp th� mQt chi�u c6 dQ
l�p I� 2a.
llJC
nao hi�n hfru d� d§n di�n nen polyacetylene la chiit each di�n. Khi them m9t ch�t h6a h9c va
polyacetylene thl cac electron h6a tri tr& nen linh d9ng hcYn. Ch§t h6a h9c nay duQ'c di�u ch�
b�g each oxid h6a dung dich nu&c cua m9t halide kim lo:;ti ki�m c6 s6 hrQ'ng electron ben
trong cua cac nguyen tu hqp thanh b�ng v&i argon. Vi�t cong thirc h6a h9c ciia ch�t nay.
143
HU'(mgd�n
a)
--- c:1 =a-l.62P
---ei =a-0.62/J
f
f
1
&; = «+0. 6 2/3
l
&4
= a+l.62,8
b) �s = s2 - s3 = a-0.62,8-(a +0.62,B) = -1.24,B
c)
� �
� � LUMO
-
OMO
�H
•�
�
�
d) Ek (max) = a - 2,8
Ek (min) = a+ 2,8
Nlur vay khoang each nang hrQ'Dg gifra Ek(max) va Ek(min) is -4/J or 14.61
e) LUMO giam b8n do s\r ta hQ'p gifra hai orbital 2pz khac d�u.
HOMO b�n h6a do s\r t6 hop gifra hai orbital 2p2 cung d�u.
Dap: (b)
f) Br2
144
Bai 73 - H9p th� m9t chi�u
Nhi�u protein chfra cac pha:n tir porphyrin kim lo,,ti. C�u true t6ng quat ci1a phan tir porphyrin la:
a) Phan ti'r nay ph�.ng va do d6 chl'.mg ta c6 thS xem r�ng cac electron bi gi&i h�n trong mot hlnh
vu6ng. Xac dinh cac mfrc nang luong va do suy bi8n cua mot h�t trong mot hlnh vuong c6
c�nh b�ng a.
b) Phan ti'r porphyrin c6 18 n electron. N8u chung ta cho xiip xi chi�u dai phan t.ir la 1000 pm,
xa.c dinh hiip th\1 nang luQ'ng qrc d�i cu.a phan ti'r porphyrin. (Gia t:ri th\tc nghj�m la khoang
17000 cm- 1).
145
Bai 74 - H9p th� m9t chi�u
C§u. true electron ciia v�t li�u ngtmg t1,1 tlnr6'ng Ia khacv&i nguyen tir co l�p. Ching hi;1.n, cac mire
nang lm;mg cu.a chu6i mot chi�u Clla cac nguyen tfr sodium dUQ'C bigu di�n & cac hinh dtr6i day:
•
•
;
;
Na3 • • ••-:.;__
'
''
,,
..
•
.... ,/,,•-­....
,;
,:-�'
',
Cac hlnh t1:en chi ra nhtrng S\l tliay d6i cua mire nang hrqng cua cac trl;l.ng thai bit ngu6n tt'r mire
3s ctia sodium. Khoang each gifra cac mire nang lm;rng giarn xu6ng do s6 nguyen tfr N a tang len.
Khi s6 nguyen h'r sodium (N)vo cung l&n thi khoang each giua cac mire nang ltrQ'llg tr& nen rftt
nho, khong dang kS sov&i nang ltrQ'llg nhi�t. Cac electron 3s ci1a sodiwn dang chi�m cir cac mire
nang hrQ'ng th§p c6 thS doi Jen cac mire nang hrqng cao d�n t&i d�c tfnh ciia kim lol;l,i. B&i v�y,
cac electron 3s c6 thg dtrQ'c coi la nhtrng hl;l.t t\t do chuyg n dong trong hop th� mot chi�u.
a) Nang hrQ'llg cu.a cac electron t\r do chuySn dong t:rong hop th� mot chi�u dtrQ'C xac dinh theo
h� thirc:
n2h2
=
En 8mL2
Trong d6, n la s6 ltrQ'ng tir (n = 1, 2, 3, ...); h la hfulg s6 Planck; m la kh6i htQ'ng electron; L la
chi�u dai cu.a chu6i cac nguyen tfr Na mot chi�u, L = ao(N - 1)v&i N la s6 nguyen tfr Nava a0 la
khoang each gful nh§t giua 2 nguyen tfr qmh nhau. Ttm bigu thirc tinh nang ltrQ'llg cu.a mire cao
nhftt bi chi�m.
b) Cho bi�t 1,00 mg Na ti;10 ra chu6i mot chi�u v&i ao = 0,360 nm. Hi�u giua mire nang ltrQ'ng
th§p nh§tva cao nh§.t d�u c6 electron la bao nhieu?
c) N�u hi�u cac mire nang ltrQ'Ilg cao nh§.t c6 electronva th§p nhftt kh6ng c6 electron la 4. 10 ·21 J
thl s6 nguyen tfr Na (N) b�ng bao nhieu? Bi�t N la s6 ch�n.
Hmrng dfin
a) Vl m<)t trl;l,ng thai rieng bi chi@m b&i hai electron v&i spin trai d§.u (i !), s6 hrQ'ng tfr n cu.a
mire bi chi�m cao nhftt la N/2 d6iv&i s6 electron N la s6 ch�n va (N+ 1 )/2 d6iv&i N le. Chi�u
dai (L) dia chu6i: L = ao(N - 1). Tfr cong thl'.rc tfnh En, ta c6 muc nang hrQ'Ilg cao nhit c6
electron la:
+) D6iv&i s6 electron N la s6 chin:
N2h2
32ma�(N - 1) 2
EN=------
2
(1)
+) D6iv&i s6 electron N la s6 le:
146
(N
Z
Z
+ l) J,
ENH =-----­
-2_
32ma�(N 1) 2
(2)
-
b) Hi�u 2 muc nang lm;rng th�p nh§.t va cao nh�t d�u c6 electron
+) D6i v&i s6 electron N chful:
N2h2
12h2
----�E= EN-Ei=-----32ma�(N -1) 2 8ma�(N -1) 2
2
41
h2
N2 [
32ma5 (N -1) 2
(3)
+) D6i v&i s6 electron N la s6 le:
�E = EN+1 - E1 =
-2-
2 2
h 2 [(N + 1) 2 -4]
12 11 2
(N + 1) h
=
32ma6(N - 1) 2 8ma6(N -1) 2 32ma5
(N -1) 2
(4,)
+) S6 nguyen tu Na= 6,022.1023.1,00.10-3 /23= 2,618.10 19 (nguyen n'r). Vi N = 2,618.10 19 r§.t
lon, nen tu (3) va (4) ta c6:
(6'626. 10- 34)2
h2
= 1163
�E - -- =
'
· 10- 19 0)
31. (0, 36. 10-9)2
1032.9,1.
- 32ma6
c) Vi s6 nguyen hr N la s6 ch�n nen:
�E = E LUMO -E HOMO = E N
(zt1)
-
- EN
2
h2
+ - 4. 10 -21 CJ)
.
10 -19 . N 1 2 (N + 1) - 4.1,163.
2.
2
8m a 0 (N - l)
(N - 1 )
⇒ r(N-1)2/(N+l) = 116,3
⇒ LDo d6, ta c6 phuong hinh b�c hai: N 2 -118,3N - 115,3 = 0
⇒ N = 119,2::::: 120 vi N la s6 chful.
21
Do d6, 120 nguyen tir Na din d� c6 �E = EwMo -Ett oMo = 4.10- (J).
147
Bai 75 - H9p th� m9t chi�u
MQt phan tfr thrtng CH2CHCHCHCHCHCHCH2 khi bi chi�u xi,t. b&i photon sinh ra b&i s\r
chuy�n tu tr�g thai kfch thfch thtr 6 v� tr:;ing thai ca ban cua nguyen tfr hydrogen th} c6 th� t:;io
thanh m9t ph6 h�p th1,1 hay kh6ng? Hay giai thfch b�J1g tlllh toan. N�u c6 th�, hay tinh bu&c song
C\fc d:;ti; n�u kh6ng th�, hay giai thfch t:;ti sao.
Hmmgd§n
Nang hrQ'ng ci'.la photon sinh b6i b6i nguyen tfr hydrogen chuy�n tu tr:;ing thai kich thich tln:r 6 (n
= 7) v� tr:;ing thai ca ban (n = 1) la
1
7-
1
1-
48
49
MH =-13.595x--i eV- (-13.595x-:,eV ) =13.595x-eV
� 13.32eV � l.285xl06 l•mor 1
Nang luQ'l1g t6i thi�u c§n cho ph6 h§p th1,1 cua phan tfr CH2CHCHCHCHCHCHCH2la
9x( 6.626x10-34 J •sf
=-------------2
8x 9.1095x10-3 ! kg X (1120x Hr 12 m )
= 4.282x10- 19 J
= 2.579 X J {)5] •mor 1
Ro rang LiE H > �Ec8• Theo guy t�c ltrQ'ng ttt h6a, CH2CHCHCHCHCHCHCH2 kh6ng th� t:;io ra
cac bi�u rrng b§p th1,1 anh sang. D@ ti;io ra ph6 h�p thµ thl ngu6n sang phai dtrQ'c thay th�, vf d\1
nlm bfulg each thay th� ph6 nguyen tfr hydrogen b�g ph6 lien tµc. Luc nay, dieu ki�n luong tfr
h6a se duqc th6a man. Phan tir lien hqp c6 th8 t,;1,0 thanh ph6 th§p thµ voi bu&c song h§p thµ la:
A.= he= 6.626xl0- 34 J•sx 2.998x10 8 m•s- 1
�E
9x( 6.626x10-34 J•s'f
8x 9.1095x10-31 kg x ( l 120x10- 12 m)
= 460nm
148
2
HU'(mgdiin
E
hi
11 11
1 ,
2
- -(n
+n 2Y )
8ma 2
-
:x
E"x"y la suy bi8n don v&i nx= ny va suy bi8n kep v&i n x j. ny.
Energy level
(n.-,n)
Degeneracy
£,1
(I, I)
I
£12
(I, 2)(2, l)
2
Ell
(2. 2)
I
2
2
2
(3, 1)(1, 3)
£)1
(3. 2)(2,3)
Eu
£•I
(4,1)(1,4)
E) l
(3,3)
Eu
Eo
(4, 2)(2,4)
2
(4. 3)(3,4)
2
(energy level= mire nang lm;mg� degeneracy= d9 suy bi�n)
Do m6i mire nang hr(Jng c6 th� gifr 2 n electron nen h�p th\1 nang hr(Jng C\l'C ti�u v&i phan tu
porphyrin se kfch thfch 1 electron tu trc:1.ng thai E42 d�n trc:1-ng thai B43. Do d6:
lz 2
2 )
liE= 8ma2 (n 2,2+",l 2-n 2_,-11,,
,.
,.
C:
(6.626 X 10- 3• J.s)
- -----------------2 (42 + 32 - 4 2 - 22)
8 (9.11 X 10-JI kg) {1000 X 10- 12 m)
= 3.012 X 10-19 J
2
Do
E = hcv,
ii= 1.52 x 10 cm4
1
•
149
Tinh the
Bai 76 - Cfiu true hai chi�u
D9 dai lien k@t C-C trong lop phan ti'r than ehl la 142 pm. Ve c�u true O mc;111g CO' SO' hai chiSu eiia
than chi. Tfnh di�n tfch o mc;111g cO' s&.
Hmmgd�n
C�u true phan ti'.r cu.a lap than chi duqc cho ()' hlnb l a; 6 m�mg CO' SO'()' hlnh lb; va tn_lC d6i xl'.mg
bl;ic 6 & hinh le. Do11 vi do dai la pm. M6i o m<,tng c6 2 nguyen ti'r C va 3 lien k@t C-C.
(<:)
(1)
Hinh 1: C�u true l&p phan ti'r than chl.
Ch.iSu dai cac cc;111h ciia 6 m c;111g (a, b):
a= b= 2x 142pmx cos30' = 246pm
Di�n tfch o rn:;ing:
axbx sin 60" = 246pmx 246pmx sin60" = 5.24x 104 pm2
150
Bai 77 - Tinh th� kim lo�i
Cho 4 qua c�u ban kinh bfulg nhau (R), x�p ch�t khit nlm b:ong h.in.h lava lb, con hinh le bi�u
di�n si,r t�o thanh h6c tir di�n. Dinh ciia tit di�n d�u la vi trf tam ci1a qua c�u, va chi�u dai qrnh
ben b�:ng 2 1� ban kfnh qua du.
D
(b>
{a)
(C:)
Hlnh 1
H�y tinh (theo R): do dai c� va chi�u cao cu.a tir di�n; khoang each tt'r tam d�n d.inh� do cao ciia
tam tinh tt'r m�t day, g6c giil'a tamva hai d.inh; khoang each ng�n nhfit tt'r tam d�n qua du.
Hll'6'ng d§n
n
Chi8u dai c�nh AB=2R
Chi�u cao:
AM=(AE'-EM'i
=[AB'-BE'-GDE
2
= ./6R� 1.633R
3
Khoang each tt'r tam d�n d.inh:
OA=IAM=
4
./62 R�d.225R
Do cao cua tam tfnh tt'r m�t day:
OM= _!_AM=
4
./66 R�0.408R
G6c giua tamva hai d.inh: LAOB
151
_, 2(./6R12/-(2R)
[0A +OB -AB ]
0 = cos ------ = cos [
j
2( OA)( OB)
2(✓6R/2 r
_1
2
2
2
2
= cos- 1 (-113) = 109.47°
Khoang each ngfu1 nh§t ht tam dBn qua cAu = OA- R � 0.225R
K8t qua tfnh toan cirn cau hoi nay co y nghia quan trc,mg b&i u't day ta c6 th8 thfty rfulg 0.225R la
ban kfnh qrc dzj cua mot qua c§u nho c6 th8 xBp khft vao h6c tu di�n t,;io thanh b&i cac qua c§u
b�ng nhau c6 ban kinh R.
152
Bai 78 - Tinh th� kim lo�i
Cho 6 qua cAu ban kinh b�ng nhau (R) x�p ch:,it khit nlnr trong hlnh 1 a va 1 b, con hlnh le bi�u
di�n S\f t:;to thanh h6c bat di�n. Dinh ciia bat di�n la tam qua cAu va dQ dai c:;i.nh Clla n6 b�ng
du&ng kf nh qua cAu. Th� tfch th\rc t� cu.a h6c nho hO'n th� tfch bat di�n. Tfnh khoang each qrc
ti�u tir tam ci'.la h6c bat di�n d�n qua cftu (theo R).
F
(c)
(bl
(a)
Hlnh 1
Tl'r hlnh (c), khoang each tir tam ciia h6c bat di�n d�n dinh la
✓
✓
OC= .!_AC= _!_ 2,AB = .!. 2,x2R=
2
2
2
✓2R
Khoang each ngfui nh§t nr tam ciia h6c bat di�n d�n qua c�u la:
OC- R =
✓2R- R-;:::, 0.414R
Day la ban kinh c1,rc d� cu.a mot qua d.u nh6 c6 th� x�p khft vao h6c bat di�n t:;to thanh b&i cac
qua c�u b�ng nhau c6 ban kfnh R.
153
Bai 79 - Tinh th� plantinum
Kim lo� platiunum c6 d.u true ki�u Al (con gQi la ki�u li;ip phuo·ng tam di�n), v6'i hfulg s6 m�mg
la a= 392.3 pm va kh6i lll'Q'ng nguyen tfr hrong d6i ciia plantinum la 195.0. Xac dinh kh6i lm;mg
rieng va ban kfnh nguyen tfr cua plantinum.
Hmrngd�n
Do kim lo�i plantinum thu9c ki�u cfiu true A1 nen c6 4 nguyen tfr trong m6i o m:;i.ng li;ip plurO'ng.
Kh6i luQ'llg rieng cua plantinum la:
1
4xl95.0g•mor
D= 4M =
a3 NA (392.3x 10- 10 cm )3 X 6.022x 1023 mor 1
3
= 21.45g•cm-
Trong cfiu true A1, cac nguyen tu tiBp xuc v&i nhau qua ducmg cheo ct\a o m�g l�p plmong, do
d6 m6i lien M gitra h�ng s6 m:;i.ng v&i ban 1dnh R la a= 2✓2R
a
R= 2✓2 =
392.3pm
✓2 = 138.7 pm
2
154
Bai 80 - Tinh th� nhom
Nhom c6 c�u tnk tinh th� l�p plnrong tam di�n v&i kh6i luQ'ng rieng 2.70 gram cm- 1• Tfnh h�ng
s6 m:;i,ng va ban kinh nguyen tfr. Tfnh g6c nhi�u x:;i. & m:;tt 333 dm;rc do b&i phuO'ng phap nlri�u x:;i.
b9t ti.a Cu Ka..
Hmrngd�n
Oi.u true tinh th� ci1a nhom la l�p plnr011g tam di�n, do d6 c6 4 nguyen tir trong 6 m�ng cO' s&.
M6i I ien h� giua kh6i luQ'ng mol M ctia nhom, h�ng s6 m�ng a, kh6i luQ'ng rieng D va s6
Avogadro NA la:
Do d6 h�ng s6 m:;mg la:
4
( M
a= DNA
J
I
3
1
4x26.98g•mor
= ( 2.70g•cm- 3x6.022xl023 mor 1
=404.9pm,
J
I
3
M6i lien h� gifra h�ng s6 m�ng va ban kfnh nguyen ti'r R trong c§.u true m:;ing l�p phuO'ng tam
di�n la a = 2 ✓2R , do d6 ban kinh nguyen tir nhom la:
R _ _!!___ 404.9pm _
1 43 · 2pm
- 2 ✓2 - 2 ✓2 -
Theo phu011g trinh Bragg:
A,
. 0 =-Sill
2dhkl
.
SID 0 =
A.Jh2 + k2 + l2
2a
I
154.2pm.x(3 2 +3 2 + 3 2 )2
=----"---------"-=0.9894
2x404.9pm
0 = 81.7 °
155
Bai 81 - Tinh th� silicon
C§.u true ci1a silicon gi6ng nlur kim cuO'ng, va ban kinh c9ng h6a tri ciia 116 la 117 pm. Xac d:i,nh
thong s6 m:;ing, th@ tich o m:;i.ng va kh6i luqng rieng ci1a silicon.
Hll'6'ng d§n
C6 8 nguyen tu silicon trong o m?ng l�p plnmng ciia silicon va s\r ph6i t1i ciia chung gi6ng 11.lm
cac nguyen tu carbon trong o m?ng I�p phuO'ng kim cuong. M6i lien h� gifra ban kinh cong h6a
tti cu.a silicon v&i hfulg s6 m:;i.ng c6 th@ duqc suy ra n'r dQ dai du6'ng cheo o m:;i.ng. Gia su r�ng
ban kinh c()ng h6a tri rsi va h�ng s6 m?}1g la a. D() dai du6'ng cheo la 8rsi va cung b�ng . Do d6:
a=
8
8
r;:; rs·· = r;:; x 117 pm= 540 pm
"3 " "3
Th& tkh o m?ng:
V =a 3 =(
1
x117 pm)' =l.58xl08 pm3
Kh6i luQ'llg rieng ci1a tinh th&:
D=
8x8.29g•nwr'
23
0
( 1xll7x!0-' cm)' X 6.022x10 nwr'
= 2.37 g•cm- 3
C�u true tinh th& cirn kim cuong, silicon va tlri8c xam duqc goi chung la ki@u l�p plurang kim
cuong, la mQt ki�u c�u true r6ng v&i ti l� bi chi8m b&i nguyen tir chi8m la 34.01 %.
156
Bai 82 - Tinh th� titanium
Cac nguyen tir titanium sip x�p theo ki�u cfiu true h,1c phuO'ng d�c khft v&i ban kf.nh nguyen tir
titanium la 146 pm. Ti'nh cac h�ng s6 m�.ng 1\lc plurong li tu&ng va kh6i lm;mg rieng tinh th�.
HU'(mgd�n
Caching s6 m::mg:
a= b= 2R = 2xI46pm = 292pm
c=
4
3
✓6 R = '!..J6 xl46pm = 477 pm
3
Kh6i hrong rieng tinh th6:
2M
D=-----abcsin 120 °x NA
2x47.87g•mOZ- 1
_
2
1
23
10
0
- ( 292xlo-' cm } x ( 477x 10- cm)x �x6.022xl0 nwr
= 4.51g•cm-3
157
Bai 83 - Tinh th� titanium
0 nhi�t dQ thiip h011 882.5°C, titanium k�t tinh theo kiSu h,1c plurong ch�t khft. Chiip nh� cac
nguyen tfr titanium c6 hinh c§.u, ban kinh R .
a) Xac d:inh s6 ph6i tri ciia titanium.
b) Ve 1 o m:;ing dcm vi, cho bi@t s6 nguyen ti'.r trong 1 o m:;tng. Tinh thS tfch 1 o m:;ing theo a,
R. (a la thong s6 m:;tng hay chi�u dai c:;inh day hinh h,1c plm011g).
c) Tinh d() d�c khit cua 6 m:;ing.
d) M()t m§u tinh thS titanium trong th1,tc t@ duqc xac d:inh c6 a ;;;;; 295.03 pm; chi8u cao 6
m<;lllg la 465.31pm. Tinh thg �y c6 C�ll true h,ic phuang hoan hao hay khong?
Hmrng dfin
a) S6 ph6i trf: 12
b) S6 nguyen tfrtrong 1 o dcm vi;;;;; �xl2 + ix3 + 3;;;;; 6 nguyen tfr.
Ta c6: a ;;;;; 2R ⇒ OA ;;;;; 2R, AH ;;;;; R
Ap d1,mg dinh Ii Pythagoras v&i tam giac OAH ⇒ OH;;;;; ../3R
G la tn;rng tam tam giac & day ⇒ OG = �OH = � -./3R
3
3
Ap d1,mg dinh H Pythagoras len tam giac OGI ⇒ IG ;;;;; �3 "'6R
Ma h ;;;;;2JG ;;;;;��R
3
Sttay = 6.../3R 2
V;;;;; Sttay x h = 24v'2R 3 ;;;;; 3-/2a3
c) D() d�c khit o m<;lllg:
a
3
� ··
)
£)9 d�c = v n�uyen
ttt = 6('.!:nR
.J
= 0.74 hay 74 %
V O llli,lllg
24../2R 3
d) Theo ly thuy@t, trong m:;ing tinh th8 hoan chinh:
�;;;;; �R;;;;; 1 .63
a
2R
Trong m§.u v�t thl: � = 1.58 < 1.63 ⇒ tinh thS khong hoan chinh.
a
158
Bai 84 - Tinh th� sodium
Sodium c6 m�g tinh th� li;ip plurong tam kh6i v&i a = 429 pm. Tfnh: a) ban ki.nh nguyen tfr; b)
kh6i luQ'ng rieng If thuy�t cua sodium; c) khoang each cac m�t (110). Cho bi�t kh6i luQ'ng
nguyen tit hrong d6i dia sodium la 22.99.
Hmrngd�n
a) Trong du true l�p plnrong tarn kh6i cua sodium, cac nguyen tit ti�p xuc v&i nhau theo lnr&ng
ducrng cheo trong o m�ng ca s&. M6i lien h� gitra ban kfnh nguyen ttr va hfulg s6 m�g la:
r=
.!_ ✓3a
4
Thay cac dfr ki�n vao:
✓3 429pm= 185.Spm
r= -x
4
b) M6i o m�ng ca s& c6 chl'.ra 2 nguyen tir:
M =
2 x 22.99g•mor 1
D = 23
a NA ( 429 X 10-• 0 cm )3 X 6.022x1023 mor 1
a)
d
(110) =
m
429p
a
r;::;
112
=
= 303 • 4pm
"2
( I 2 + 1 2 + 02 )
159
Bai 85 - Tinh th� tantalum
Kim lo� tantalum k�t tinh & d�ng c�u tnk tinh th� l�p plmO'ng tam k116i v& i a = 330 pm. Tfnh: a)
Ban kfnh nguyen tir Ta; b) Kh6i hrc;mg rieng Lf thuy�t c11a tantalum, bi�t kh6i hro-ng nguyen tu
tuong d6i cua Ta la 181; c) Tfnh khoang each cac m�it (110); d) Tfnh gia tri g6c nhi�u x� cua m�t
220 n�u sfr d\mg m(,t ti.a c6 bu&c song 'A.= 154 pm.
Hll'mtg diin
a) Ban kfnh nguyen tu tantalum:
r = .!_
4
✓3a = ✓3
x 330 pm= 143pm
4
b) Kh6i hrQ'llg rieng li thuy�t cu.a tantalum:
M =
2x I8lg•mor
D = 23
a NA (330x 10-10 cm)3 X 6.022x 1023 mor 1
1
c) Khoang each die rn�t 110:
a
330pm =
233pm
== =
d( IIo) = �;:::==
..j}2
r;:;
2
2
+1 +Q
v2
d)
sin 0,-20 =
A
2d(2 20
)
= -- -A__ = A = 154 pm = 0.6598
2x
1
2
d(110)
d(110)
330pml
.Ji
160
Bai 86 - Tinh th� nickel
a) Bi�t rfulg kim lo�i nickel k�t tinh theo m9t ki�u d.u true tinh th� Al v6i dQ dai ti�p xuc gitra
cac nguyen tu la 249.2 pm. Tfnh kh6i lm;rng rieng ciia Ni va cac h�ng s6 m:;ing l�p plmong.
b) Bi�u di�n s\r sip x�p cac nguyen tu t:rong cac mM () 00), (I IO) va (111).
Hll'&ng d�n
a) Do kim lo� Ni c6 d.u true ki�u A I (l�p plm011g tam di�n) nen cac nguyen tu ti�p xuc v&i
nhau theo dm:mg cheo cua o m:;ing l�p plm011g.
a::: ✓2 x 249.2pm::: 352.4pm
6 m�ng CCI s& Ni c6 4 nguyen tu, do d6:
4M =
4x 58.69g•mor 1
D::: 3
a NA (352.4x10· 10 cm)3 x6.022xl023 mor 1
::: 8.9lg•cm-3
b)
0
(100)
( 111)
I 110 )
161
Bai 87 - Tinh th� lithium
Tinh th� lithium k�t tinh theo ki�u d.u true l�p pluro-ng. Khoa.ng each (JOO) la 350 pm va .kh6i
luQ'llg rieng tinh th� la 0.53 gram cm-3. Tinh s6 nguyen tir c6 trong 6 m:;ing C(Y SCI va xac dinh
lithium thu9c .ki�u m:;ing tinh th� nao. Cho bi�t kh6i luqng nguyen tfr tuong d5i cila Li la 6.941.
Hmmgd�n
H�ng s6 m�g cila 6 m:;ing l�p plmO'ng lithium la:
a= d( ,oo) = 350pm
S6 nguyen tfr lithium c6 trong 6 m:;ing la:
Z=
0.53g•cm-3 x (350x 10-io cm }
3
6.94lg•mor' X (6.022x 10 23 mor')
-I
= 1.97 :;:: 2
Kim lo:;ii chi t6n t:;i.i & d:;ing tinh th� tap plmO'ng tam di�n ho� tam kh5i. Trang tnrcmg hop d�u,
s6 nguyen tu trong 6 m:;ing CO' s& la 4, tnrcrng h<;Yp sau la 2. vay lithium k�t tinh theo ki�u c�u
true m:;i.ng lap phuO'ng tarn kh6i.
162
Bai 88 - Tinh th� thi�c xam
ThiBc xam kBt tinh theo ki�u m�ng tinh th� kim cuang v&i 8 nguyen tfr trong 6 ml;lng ca s6' va
h�ng s6 m�g a = 648.9 pm.
a) Xac dinh t<;>a do 8 nguyen tfr trong 6 ml;lng CO' SO'.
b) Tfnh ban kf nh nguyen tit.
c) Kh6i luQ'ng rieng ciia thi& xam la 5.76 gram cm-3, t1m kh6i ltrQ'llg nguyen tir ci1a Sn.
ThiBc tring thu(>c h� ttt plmO'llg v&i a = 583.2 pm, c = 318.1 pm, c6 4 nguyen tit trong 6 ml;lJlg ca
SO'.
d) Trong qua trlnh chuy8n tl'r thiBc t.rttng sang thiBc xam th1 th� tfch 6 m�ng tang hay giam?
e)
Do dai Sn-Sn ngttn nh§t trong thi�c tdtng la 302.2 pm. So sanh v&i dft li�u ci1a thi& xam. S6
ph6i trf ciia thi& trong dl;lJlg tlu\ hinh nao cao hon?
163
HU'(mgd�n
a) T<;>a d() cua 8 nguyen tir: u
b) Ban kfnh nguyen tt'r:
IS11(�)
:::
✓3 a::: ✓3 648.9pm::: 140.5 pm
8
8
X
c)
3
M
= Ds,i("JJ<.f NA
z
3
5.75g•cm-3 x( 648.9x10- 10 cm ) x 6.022 x1023 mar'
:::-----------------::: l I8.3g•moZ-'
d) Kh6i luong rieng thi8c tdmg la:
Ds11(s) _ a2cN
4M
A
4 x 1 l 8.3g•mor'
=-------------------( 583.2x Hr' 0 emf X (318.lx Hr' 0 cm)x 6.022x l013 mor'
= 7.26g•cm- 3
Ro rang, tfr thi8c tcing chuy�n thanh thi8c giam thl kh6i luQ'ng rieng giam va th� tich tang len.
e) DQ dai Sn-Sn ngfu1 nhfu trong thi8c xam la:
2r5,.(h<) = 2x140.5 pm= 281.0 pm
Gia tri nay th�p hon so v6i trong thi& tr�ng, c6 th� th�y rfu1g s6 ph6i trf cua cac nguyen tt'r trong
thi�c tdmg cao han.
164
Bai 88a - H�p th1;1 hydrogen
Khi hydrngen & n.hi�t d◊ phong d� "hoa tan" vao rn◊t s6 kim lo�i C\l th�, vi d\l nlur palladium. 6
m�ng cCJ s& cirn palladium c6 d�g li;ip phuong, duQ'c bi�u di�n nl1u hinh du&i. Tam cua ca ca c.
nguyen tfr palldium d�t & cac dinh va cac tam m�t cua hinh li;ip plmO'ng (ca.c nguyen hr dUQ'C xem
nlnr nhung qua du cirng). Kh6i lm;mg 1ieng cua palladium la 12.02 gram/cm3, kh6i hrqng mol la
106.4 gram/mol.
1) Tinh s6 nguyen tir palladium 1rnng 1 6 rn�g cCJ s&, d◊ dai c�nh (a) va ban kinl1 c1ia cac.
nguyen tfr palladitun (r) theo pm (1 pm = 10- 12 m).
2) Gia sir r�ng cac nguyen tir la nhir.ng qua du ct'rng, tinh ban kinh nguyen tfr C\?C d� c6 th� Vl'ra
khit v&i cac khoang tr6ng (h6c) gitra cac nguyen ti'.r palladium b:ong m�ng tinh th�.
3) Khoang each lien nhan trong cac phan tir H2 la 74 pm va ban kinh cua nguyen tfr H la 54 pm.
Hydrogen trong m�ng tinh th� palladitun t6n t� & d�g nao - nguyen tfr, phan ti'.r hay ca hai?
4) Tinh s6 nguyen tir hydrogen ci,rc d� c6 th� l�p vao 6 m�ng cCJ s& palladium.
165
HU'Cmgd§n
1) Th� tfch I mol palladium la
106.4
=8.852 cm 3 / mol
Vru = M =
p 12.02
Tt'r hinh ve tren, c6 th� th�y t6ng s6 nguyen tt'r palladium b:ong 1 ornc;1I1g ca s&b�ng:
l
1
6·-+6·-=4
2
8
8·852 4
· =5.88·10-23cm 3
ThStichorn�ngcas&la: V= VF\! ·4=
23
6.02·10
NA
Chi8u dai O rn�ng Cc:J SO' la a=
w = 3.89 · l o-s cm = 389 run
T1r hinh ve tren, c6 thS thfty ducmg cheo cua rnM hinh lap plm011g lab= 4r. Ap di,mg dinh li
..,
.,
.,
,,
2
a
Pythagoras, ta c6: b- =a-+c- => l 6r- = 2a => r= r::: = 138 nm
2-v2
2)
166
a-2r
389-2·138=
r =-=--- 57nm
01
2
2
3) Hydrogen trong ti.nh th� t6n t� & d�mg nguyen tir do phan tu hydrogen kh6ng th8 Vl'ra v&i ca.c
h6c ti.nh th8.
4) T6ng s6 h6c bat di�n: 1 (& tfun ltinh l�p phuong) + 12· l/4 (& gifra cac c:;inh) = 4
Day ciing chinh la s6 nguyen tu hydrogen c�c d:;ii c6 tl1� l�p diy 6 m:;ing ca s&.
167
Bai 89 - HQ'p kim Cu-Zn
MQt hc;rp kim d6ng chua 75 % Cu va 25 % Zn v� kh6i luQ'l1g c6 kh6i lmmg rieng tinh th� la 8.5
gram cm·3• Tinh th� thUQC d.u true tinh th� l�p plm0'11g tam di�n,va O m:;ing C(J SO' chua 4 nguyen
tu. Kh6i hrQ'l1g nguyen tu tuong d6i cu.a Cuva Zn l§u lm;rt la 63.5va 65.4.
a) Tlnh ph§n mol Cuva Zn.
b) Tinh kh6i lm;rng m6i o m�ng cos&.
c) Tinh th� tfch o m�ng.
d) Tfnh ban kinh nguyen tt"r trung b1nh.
Htr6'ng dfin
a) D�t phftn mol cua d6ng trong hqp kjm la x tht phftn nguyen tu cu.a k�m la 1-x.
63.5x: 65.4(1- x) = 0.75: 0.25
Do d6:
x = 0.755, 1- x = 0.245
Ph§n mol ct\a Cuva Zn trong hqp kim l§n lm;rt la 75.5 %va 24.5 %.
b) Kh6i luqng m6i o m,;lng:
(0.75x 63.5g•mor 1 + 0.25x 65.4g•mor 1 )x 4
6.022x10- mor'
?
3
= 4.25 X] 0-22 g
c) Th� tfch o m,;lng:
V=
4.25x10-22g =
5.0x10 -23cm3
8.5g•cm-3
d) H�ng s6 ml;lllg c6 th� duqc tinh tt'r th� tfch o m:;i.ng:
I
1
a= V 3 = (5.0x 10 -23 cm3 )3 = 368pm
Ban ldnh nguyen tt"r tnmg binh:
r=
a
368pm
✓2
✓2 130pm
2
2
-;;;;;
-;;;;;
168
Bai 90 - Nhi�u x� tinh th�
H�ng s6 6 m�ng c<Y s6' ctta kim lo�i nickel la a= 352.4 pm. Tfn.h d200, d 111, d220.
HU'(mgd�n
M6i lien h� gifra chi s6 nhi8u x� h, k, 1 Clla h� l�p pluro-ng va khoang each dhkl la:
Dod6:
2 -�
2
d200 = a ( 2 ) =
2
1
2
d111 = a ( 1 2 +1 +1
a= l 76.2pm
2 )- 2
f;;
= alv3
= 203.Spm
d220 = a( 2 + 2 ) 2::: al
2
2
✓8 ::: 124.6pm
169
Bai 91 - Nhiiu x� tinh thi
Phan tit Ss c6 th� t�o thanh hm huyn.h dO'n ta ho�c hm huynh tnJc thoi. Cac h�ng s6 m�ng cO' s&
cua tinh th� hm huynh tn,rc thoi duqc do b&i nhi�u x� tia X (Cu Ka.) la. a= 1048 pm, b= 1292
pm, va c = 2455 pm. Sulfure c6 kh6i hrqng rieng 2.07 gram cm·3 va kh6i luQ'ng nguyen tu hrO'ng
d6i la 32.
a) Xac dinh s6 phan tfr Ss trong m6i o m�ng cO' s&.
b) Tinh g6c nhi�u x� Bragg & m�t 224.
Hll'01tg d�n
a) Theo cong thuc v� s6 phan ttr Z trong o m�mg CO' s&:
Z=NAVDIM
::: 6.02xl023 mor 1 (1048x 1292x 2455) pm3
=16
b) V&i tinh th� tn.rc thoi:
2
r
2
d,� = [(-l.-;4-8-2 +-1.-:9-22- +-2.:- 5\
- -,}-01 -6�
- m
- ,
-
[
= (3.642+2.396+2.655)x
6
l ]
IO pm
=339.2pm
0=sin-
1(
154·2Pm )=
13.14°
2x339.2pm
170
2
2
Bai 92 - Nhi�u x� tinh thi
a) c!u true tinh th� ci1a silicon ttrong t1,r nlnr ki m ctro·ng. H�n. g s6 m�ng l�p plnrong a = 543.089
pm, kh6i hrc;mg rieng la 2.3283 gram cm-3 Vl:t kh6i ltrQ'llg nguyen tir ttwng d6i Clla Si la 28.0854.
D\ra vao nhtmg du ki�n n ay, hay tinh gia hi h�ng s6 Avogadro.
b) Bi�t rfulg h�ng s6 6 m�g l�p plurO'llg cua tinh th� NaCl La 563.94 pm, g6c nhi�u x:;i 8 & m�t
111 do dtrqc la 5.10 °. Tinh btr&c song dtrqc sir d\mg cho thf ngh.i�m nhi�u x:;i nay.
c) Du ki�n tinh th� hc;>c cila protein ribonuclease-S nlnr sau: th� tich 6 m:;ing cos& la 167 mm3, s6
phfu1 tfr n·ong 6 m�ng cos& la 6, kh6i lm;rng 1ieng 1.282 gram cm-3. Bi�t protein chi�m 68 %
kh6i lm;mg tinh th�, tinh kh6i hrqng phan tir ttwng d6i cua protein.
Hmrng dfin
a)
NA =ZMIVD
1
8x28.0854g•mor
=----------------3
30
3
3
3
(543.089 pm ) x(10- cm • pm- )x2.3283g•cm-
= 6.0245xl0 23 mor'
b)
d,,k, = al( h +k +1 2 )2 = 563.94pml ✓3 = 325.59pm
2
1
A= dx2sin 0 = 325.59pmx 2xsin5.10 ° = 57.9 pm
= 6.022x l0 23 mol· 1 x167x 10-21 cm 3 x l .282g•cm- 3x0.68/ 6
=14612
171
Bai 94 - Nhiiu x� tinh thi
Tinh th� CaS c6 du tn'.lc ki�u NaCl, kh6i hrqng 1ieng b�ng 2.581 gram cm-3, kh6i luQ'llg nguyen
tu tuO'ng d6i ciia Cava S l§n hrQ't la. 40.08va 32.06.
a) Nhung mi;tt nao trong s6 100,110,111,200,210,211,220,222 c6 th� xay ra nhi�u x�?
b) Tfnh h�ng s6 m�ng a.
c) Tmh g6c nhi�u x� qrc ti�u c6 th� quan satduqc v&i bl'.rc x� Cu Ku(}..= 154.2 pm).
ffU'(Yngd�n
a) 111,200,220,222
b) Tnr&c tien,tfnh th� tfch o m�g:
v- MZ _
4( 40.08+32.06)g•mor 1
- NA D - 6.02 X 1023 mor I X 2.58 lg•cm- 3
22
= J .857 X J 0- Cm3
I
I
a= (V)3 = (185.7 x 10-24 cm-3 )3
= 5.705x 10-s cm
=570.5pm
c) Nhi�u x� cl,l'c ti�u quan sat duqc la v&i l 11.
I
t1i, 1 = a/(1 + 1 + 1)2 = 570.5pm/ ✓3
=329.4pm
0 = sin-' ( .-1,/2d) = sin-' (154.2pm/2x 329.4pm) = 13.54°
172
Bai 95 - Nhiiu x� tinh thi
MQt kh6i dO'n tin.h th� vang (Au) c6 di;rng l�p plnro-ng v&i chi�u d a i c� la a = 1 .000 cm. Khi
nhi�u X:;t v&i tia X Cu Kai (/\ = 154.05 pm) & g6c e = 10 .89 ° th1 t:;to ra hlnh anh nhi�u X:;t b �.c mQt
d� xac dinh. Kh6i lm;mg mol cua Au la MAu = 196.97 gram.mot· 1•
a) C6 bao nhie u nguyen tfr vang trong kh6i l:lp plm011g?
b) Tfnh kh6i lu<Jng mQt o m,;1ng ca s& vang.
c) Tfnh kh6i lm;mg rieng c1ia vang.
Hu-011g d§n
a) van dl)Jlg dinh lu:lt nhj�u X<;l Bragg, 11. A = 2a. sin0, dB xac dinh h�ng s6 m,;1ng Clla Au:
n"A.
a=-2sini0
1><154.05x10- 12
2 sin(l0.89° )
a= 4.077 X ] o-tO m = 4.077 X 1 o-S CID
ThB tfoh Clla mot o m,;mg Cc:J SO' Au la
S6 o m:;ing ca s& c6 trong 1.000 cm 3 la
N.,,,
LOOO
22
23 =L476xl0
6. 777 X )Q-
C§u true o m:;ing tinh thB I�p plnr011g tam di�n
Cac nguyen tfr 6' g6c thu<'.>c v� 8 o mi;ing, tuO'ng du011g v&i m6i o m:;tng c6 1/8 nguyen tfr g6c; cac
nguyen tfr 6' m�t thu<'.>c v� 2 o m:;ing, tuong du011g v&i m6i o m:;ing c6 1/2 nguyen tu m�t. V�.y
m6i O m:;tng CO' SO' C6 4 nguyen tfr, llu = 4.
173
1
l
n =8x-+6x-=4
l
l
8
2
S6 nguyen tu Au trong kh6i l�p plnrong 1.000 cm 3 la
NAU =
N X nu = 1.476 X 1022 X 4 = 5.904 X 10 22
b) Kh6i hrong mot nguyen tir Au la
mAu =
196.97
=3.27) X to--,,- g
=---23
6.002214 X 10
NA
M Au
Kh6i luQ'Ilg 6 m:;i.ng C(J SO' la
M u = D u IDAu = 4 X 3. 271 X 10-21 = 1.308 X l 0 -21
g
c) Kh6i hrQ'llg rieng ciia Au la
dAu = N Mu= l.476 XI 022 X 1.308 X 10-21 = 19.31 gcm-3
174
Bai 96 - St;r �o thanh epitaxy
MQt l&p mang mong b�ng vang barn tren m9t manh mica hlnh vuong, chiBu dai c:,mh a = 1.000
cm. L&p mang nay t:;to ra mQt du true bB mM ly tu6ng (100). Ngam l&p vang nay va mQt SQ'i day
vang vao 10.000 cm 3 dung dich di�n phan chira CuSO4 va Na2SO4, c6 n6ng d9 dBu la 0.100 M.
D�t m<'.)t di�n ap kh6ng d6i vao gifra hai di�n qrc, l&p Au(l00) dong vai tro nlm cathode, con sQ'i
day vang la anode. M<'.)t l&p epitaxy' Cu g6m 100 dO'n l&p duqc t�o thanh tren ch§t nBn Au(lO0).
Vang c6 du true tinh th� Hip plnrO'ng tarn di�n (fee) v&i h�ng s6 m:;tng la 4.077· 10-8 cm. Tfnh
n6ng d() c11a CuSO4 trong dung dich di�n phan sau khi l&p epitaxy Cu duqc t�o thanh.
HU"011g din
i) Xac dinh s6 nguyen tir Au trong hlnh vuong dai 1.000 cm c6 c�u true b8 m�t (100).
Di�n tfch cua b8 m�t Au(lOO) la:
Cac nguyen tu a g6c thu9c v� 4 6 mc;1ng CO' sa, tuO'ng duO'llg v&i m6i 6 m�ng c6 1/4 nguyen tir
g6c; ngoai ra con m9t nguyen tir a gifra. Do vay, m6i 6 mc;1ng CO' sa bB m�t c6 2 nguyen ti'r Au:
1
n u ""4x-+1""2
4
S6 nguyen tir Au (m�t d<'.) nguyen tu bB m�t) trong 1.000 cm2 b� m�t Au(l 00) la
0Au(IOO)
Du
"1,
= A = 1. 662 X ] o-lS
u
-----
= J.203 X 1015 Cm-2
ii) Xac dinh s6 nguyen t1r Cu trong 16p epitaxy.
L&p ch�t nBn Au(l 00) dong vai tro nlnr m9t cai khuon (miiu) d6i v&i S\! tc;lo thanh epitaxy, thS
nen l&p Cu c6 c�u true gi6ng h�t ch�t nSn. Do v�y, s6 nguyen tfr Cu trong m<'.)t don l&p b�ng
I .203· 10 15 va s6 nguyen tir Cu trong epitaxy la
Neu= ]00 x 1.203 X 10 15 = 1,203 x 1017
S6 mol Cu t:;to thanh (trong epitaxy) la:
cu
D
= N ClJ = 1,203 X 10'7 = 1.999 '.)( 10-1 mol
N
6. 02214 )( 1023
A
iii) Xac dinh s6 mol CuSO4 trong dung dich ch�t di�n Ii sau khi tc;10 thanh l&p epitaxy.
1
Lop phu tinh th�, g6m nhi8u don l&p
175
S6 mol CuS04 trong chftt di�n Ii sau khi t�o thanh l&p epitaxy b�g s6 mol CuS04 ban d§.u tnr di
s6 mot Cu t�o thanh tren chftt n�n Au(l 00).
-4
"cu ""' 1.000 x I 0
iv) N6ng
x 10.000 x 1cr3 - 1.999 x I 0-7 ""'8.00] x 10-7 mol
do CuS04 sau khi t�o thailh l&p epitaxy:
Ccuso • =
8.001 x 10-1
I 0. 000 x 1 o-3
= 0. 0800 mM
176
Bai 97 - V�t li�u sieu d�n
Nam 1986, Georg Bednorz va Karl Mi.tller, trong th<'Yi gian nghien cm1 t� IBM Zmich , da kham
pha ra tinh sieu dfu1 cf1a v�t h�u lanthanum baiium copper oxide (LBCO) & nhi�t do 35 K, nhcr
d6 hQ danh duqc giai Nobel V�t li nam ti�p theo. Cung trong nam 1987, Maw-Kuen Wu va Chu
Ching-wu cung cac h9c t:ro 1::;li DH Alabama, Huntsville, da phat hi�n ra r�ng yttiium ba1ium
copper oxide (thm'mg ki lu�u la YBCO) la. ch§,t sieu dfu1 & t:ren 90 K - mot muc nlu�t da gia tang
dang k8 va c6 tfun quan tr<;>ng b&i 116 n�m tren di8m soi ci'.la nitrogen long (77 K , rnuc nhi�t do
lam h;mh kha tlu trong th,rc t�). Cac m§u d:lu ti.en t6ng hqp duqc c6 c6ng thuc Y 1.2Bao.&Ct104 tuy nluen, day la thanh phfu.1 hung binh Clla hai phase: mot phase rnau den va phase con 1� man
xanh du011g. E)� xac dinh cac phase nay, Chu da nhcr t6i Dave Mao va Robert Hazen & Phong thl
nghi�m Dia V�t li t� Vi�n Carnegie, Washington. Ho th§y dng, phase mau den (chinh la ch§,t
sieu dfu1) c6 thanh ph:ln YBa2Cu301-o. Kham pha nay da tln'.1c dAy nhtmg 116 hrc ngluen cl'.m trong
vi�c tim ki�rn tinh sieu elfin & nhtmg muc nlu�t do cao hon - li tu&ng nhftt la nlu�t do phong, d11
r�ng v§n rftt kh6 d8 dc;tt duqc.
a) Du6i day la 6 m�ng ca s& cua mot tinh tl1� YBCO li tu&ng. Xac dinh nhtmg hinh tron 1:tr011g
l'.mg voi nhung nguyen t6 nao trong c�u true nay?
a
C§u h11c tlwc sv cua v€it h�u la t11rc thoi (a :f:. b :f:. c) nlumg rftt g:ln d�ng tl'.r plur011g, v6i a� b �
c/3.
b) Ngluen cuu mot m§u YBCO c6 8 = 0,25 b�ng nlu8u Xc;l tia X v6i bt'rc Xe;\ CuKa. (A.= 154,2
pm). Peak nlu8u xc;t & g6c nho nhftt l'.mg v6i 20 = 7,45° (0 d<;>c la tl1eta). Gia sir r�ng a = b =
c/3, hay tinh cac gia hi cirn a va c. Tinh kh6i lm;mg 1ieng ct\a m�u YBCO (8 = 0,25) theo g
cm-3. Cho biM phu011g hinh nhi8u x� Bragg: sin0 = n)J2d.
177
HU'(mgdiin
a)
lJ
•
=
0
=O
Q9 -ua
0
= y
b)
.
DA
sin 0=2d
1) • (154.2m)
d= (
. =1187 pm
2sin(3.725° )
G6c nho nh§,t ⇒ d la t:11,lC dai nh§,t = c, v�y c= 1187 pm va a= c/3 = 396 pm.
Tinh kh6i luqng rieng:
Vue = a· b · C= 3a 3 = 3 · (396pm) 3 =1.836-10- 22 cm 3
1
muc = (- -)(88.91+ 2· 137.33+3· 63.55+ 6.75 • 16.00)
NA
( 662.22 gam mor 1 )
.
-21 gam
=}.100·10
23
1
( 6.0221 · 10 mor )
.
( uc = unit cell: 6 m,;111g CO' s&)
lTi uc=
(1.100 • 10-21 gam)
•A
A•
-3
Kh01 luQ'llg neng
=
= 5.90 gam cm
_2,
3
(1.863· 10 - cm )
178
Bai 98 - Carbide kim lo�i
1) Khi dw1 nong than chi v&i kim lo� potassium, thu
dm;rc hqp ch�t c6 cong thl'.rc dO'n gian nhftt KCx.
Trong hqp chfi.t nay, cac nguyen tfr K xam nh�p vao
m:;ing hr&i tinh th� c11a than chi, sip x@p theo urng l&p,
n�.m xen giua tftt ca cac nguyen tfr C. Trong m9t l&p,
cac nguyen tfr K each d�u nhau va chi@m vi t:rf phfa
tren va phia du&i tam dia m9t s6 hlnh hie giac t:;i,o vai
cac nguyen tlr C. Hinh ben mo ta du true ciia hqp
ch�t KCx nhin theo plnrong vuong goc v&i cac l&p
than chi, trong do cac l&p nguyen ur C hoan toan
O=K
t:rung nhau va cac l&p nguyen ur K cung hoan toan
trung nhau.
a) Xac dinh gia tri X trong hqp ch�t KCx.
b) Chi�u tia X co bu&c song "A. = 1.54O6A qua tinh th� KCx, tia c6 g6c l�h nho nhftt c6 gia
tri 20 = 16,402 °. T(nh kh6i luqng rieng (g/cm3) ciia KCx v&i gia thi@t do dai lien k@t C-C
trong KCx khong thay d6i so v&i than ch1.
c) Tren th\rc t@, kh6i lm;mg rieng cua KCx la 1 .948g/cm3 . Tinh do dai (nm) cua lien k8t
C-C va giai thfch S\l tlrny d6i do dai lien k8t trong hqp ch�t KCx.
2) Than chi cung co kha nang t:;i.o cac hQ'p chftt xam nh�p v&i Li. Cong thl'.rc cfra mot trong
nhfrng hQ'p ch�t do la LiC6. Cho bi@t trong LiC6, cac nguyen tfr Li phan b6 theo ki�u KCx
dUQ'C mo ta nlnr tren. Ve du tnk Clla LiC6 tbeo each bi�u di�n du true Clla KCx O' hlnh tren.
179
HU'(mgdiin
1) a) Cong thuc don gian nhfit la KCs
C6 th� hlnh dung tinh ti�n l&p K d6ng ph�ng v&i l&p C,
chQn "6 mc;tng" don vi nlnr hinh tren, trong mot do-n vi s6
nguyen tfr K = I va s6 nguyen tfr C = 8 nen cong thirc cua
KCx la KCs.
b) G<;>i khoa.ng each gitra cac nguyen tfr C la d', dm;rc tfnh
theo plurang hinh (1)
.II.
d'=--=
2s. in0
.5406
. O1)
2.sin(82
°
=5.400A
O=K
Cfr 4 dan vi nho 1lhM nlnr da chc;m & cau 1 b thl c6 1 nguyen nr K, v�y 1 dO'Il vi nay c6 0,25
nguyen nr K.
Th� tich V' cua 1 don vi la:
5 400
�=� ⇒ V'= V.�=1 .7 57 ·10-23• . = 2.832·10-23(cm3)
V d
d
3. 350
2·12+0.25-39
23
3
°rien°
la: D'= 6-022l·I023 =l .979(2/cm
)
Kh6ihron
• t:,
t:, KCs
�
2.832-10c) Goi th� tfch th1,rc cua mot dan vi da xet la V", kh6i lm;rng rieng ci1a KC& la D", ta c6:
V" D' 1.979
-=-=-V' D" 1.948
GQi do dai lien k�t C-C trong KCs la a", ta c6:
vV'
vr0
(a")' = .!"..:: ⇒ "= 0.1421· /IF=0.1421· {D'=0.1421·/·979=01432 nm
a
( )
0.14212 v·
1.948 •
Do dai lien k�t C-C tang len t:rong hqp ch�t KCs so v&i trong than chl b&i vl cac nguyen tfr K
chuy�n mot phfu1 di�n nr cua n6 sang than chl (hQ'p chfit c6 dc;tng K + c; ). Cac electron nay duqc
di�n vao cac orbital 1t pban lien k�t cua than chl va lam giam do boi Lien k�t, dfu1 d@n tang do dai
lien k�t C-C.
2) a) Cong thuc LiC6 cho bi@t cir 3 6 h,1.c giac t�o b&i cac nguyen nr C thl se c6 1 nguyen tfr Li. Ti
,
11L.
8 4
so·_,---• 11K - 6 - 3.
180
L&p nguyen tir Liva K c6 di�n tich nhu nhau. Nhu v�y, di�n tfch hlnh h;c giac Li6 =
hlnh h,lC giac K6.
Khoang each K-K trong KC8 la: JK-K = 2
✓3
.Jc-c
V�y d9 dai Li-Li t:rong LiC6 la: du-li = 3.dc-c
Nlm v�y, mo hlnh c�u true LiC6 nlm hinh ben. Ki8m
tra lc;li ti I� Li : C, ta c6: trong mot "o lilc;lllg" don vi
J
da chon, n Li = l;nc = 8.-+2 =6.
2
181
O=Li
I4 di�n tfch
Bai 99 - Cfiu true tinh th� cac hQ'P chfit silicon
Silicon oxideva thtiy tinJ1 silicon c6 cac don vi du true n6i v&i nhau b&i cac lien .k�t c()ng h6a tr:i
Si-O
a)
b)
Cho biJt s6 ph6i trf ci1a cac nguyen tfr Siva O trong cac ctu true nay
Bigt kh6i lm;mg rieng ctia thtiy tinh silicon la 2.203 g/cm3 . Cho bi�t th� t:fch trung b1nh cfia
m()t don vi SiO2? C6 bao nhieu lien kJt trong m()t don vi th� tfch trung b1nh ?
Ml;lng tinh th� ct\a thtiy tinh silicon khong hoan hao do s\r thigu h\1t oxygen: cac nguyen tfr
oxygen trong m�g tinh th� da bi mtt va cac nguyen tfr Si lang gi�ng ctia nguyen tir Si mftt
oxygen t\r b�n h6a b�ng each tl;lo lien k�t Si-Si. M§u silicon oxide v6 d:inh hinh dtrQ'c dijc tnnig
b&i c6ng thoc SiO1.9.
c)
d)
T6ng s6 lien kgt Si-Si chi�m bao nhieu phfu1 tram?
Vigt bi�u thuc bi�u di�n ti 1� nsi-s/nsi-0 trong m9t m�u SiOx nJur mQt ham cu.a x, v&i nsi-Si
la s6 lien kgt Si-Si va 11Si-0 la s6 lien k�t Si-O. Tinh gia tri Clla X khi trung binh t�t ca cac
nguyen ti'r Si d�u tl;lo m9t lien k�t Si-Si.
182
HU'(mgdiin
a) 4 va 2
b) Trong 1 cm 3 ta c6 p,NA I M(SiO 2 ) = 2.208· 1022 don vi SiO2. ThS tfch mot d011 vi la 4.53· 10·2 3
cm3 . M6i nguyen tir Si t�o thanh 4 lien kSt Si-O. Nlm v�y mot thS tfch nguyen t6 c6 1 d011 vi
SiOi g6m 4 lien kSt Si-O.
c) D�t s6 nguyen tir Si la n. Chung ta c6 s6 nguyen tu Ola 1.9n dS t�o ra 3.8n lien kSt Si-O. Gia
tri 4n va 3.8n electron h6a tri dm;rc t�o nen b&i cac nguyen tir Si va O t:,to thanh (2 + 1.9)n lien
kSt (Si-O va Si-Si). Gia t1i con 1:.ti 3.9n - 3.8n chfnh la s6 lien kSt Si-Si. Ti I� giua chung la:
3.9n-3.8n == 0.1 ==
0_0256
3.9n
3.9
Nlur v�y 2.56% s6 lien k8t la Si - Si
d) N6i chung cong thl'.rc nh� dm;rc c6 thS dm;rc viSt t6ng quat du6i d�.g:
n s. ., s_.,· =--=
2n-nx 1
_
-05
Ils;-0
2nx x ·
Tt'r cau hoi ta c6 th� doan dm;rc r�.ng ti l� lls ;.s; la 1/6. f)i�u d6 d�n d�n k�t qiia x == 1.5.
flSi-0
183
Bai 100 - Cfiu true tinh th�
Khoang cristobalite (SiO2) c6 d.u trl'.1c nlm sau: Cac nguyen ti'r Si s�p x�p CJ cac vi trf gi6ng nJm
cac nguyen tir C trong kim ctrong va CJ gitra 2 nguyen tirSi la ITIQt nguyen tir 0.
b) Ve c�u true ci1a cristobalite.
c) Xac dinh thong s6 m:;ing a bi@t kh6i hrqng rieng cua cristobalite la 2.32 g/cm3 ; M(SiO2) =
60.1 g/mol.
Hmrugd§u
a) M:;ing tinh th� c1istobalite nJm sau:
eo
Luu y: £>� bai c6 d� c�p d�n vi�c CJ gifra 2 nguyen tir Si Ja l nguyen tir 0, d6ng nghia v&i vi�c
nguyen tir 0 chi nfun CJ giua 2 nguyen tir Si "giin nhau nh�t" t:rong 6 m:;ing. Trong hlnh ve thl 2
nguyen tir Si d6 chinh la nguyen nr {y dinh ho�c {y m�t tam Clla kh6i 1ap phtrong l&n va nguyen tir
CJ h6c tu di�n dia kh6i lap plmong nh6.
S6 nguyen tirSi/16 = 8.1/8 + 6.1/2 + 4 = 8
b)
S6 nguyen u'r 0/1 6 = 16
⇒ S6 phan nr SiO211 6 = 8
8M
8M
m 11
= . 3 s;o,- => a = 3 . s;o,Ta c6 cong thl'.rc: D = D.N A
a NA
vii
Thay M(SiO2) = 60.l g/mol; D = 2.32 g/cm3 ; NA = 6.022·1023 mo1·1
⇒ a;:::: 7·10·8 cm= 7 A.
184
Bai 101 - Nang hrQ'Dg m�ng hr6i
a) Hqp ch§.t MgO k�t tinh theo cftu true ki�u NaCl, va khoang each ng�:n nh�t la Mg-O la 210
pm. Sir d\lng cong thuc dmn day d� ti.nh nang ltrqng m:;i.ng hr&i U
(P::: 0.31x 10- 10 m)
b) Ai h,rc electron thir hai cua O khong th� duqc xac dinh tnrc ti�p trong phase khi
( o- +e ➔ 02-). Sir d\lng dtr li�u du&i day vanang luQ'l1g m:;i.ng lu&i tinh duqc & (1) d� xay dwng
chu tr1nh Born-Haber va tfnh gia tri nay.
o- ( g) ➔ 0 ( g) +e
141.8kJ · maZ-
02 ( g) ➔ 20 ( g)
498.4k] · mar 1
Mg(s) ➔ Mg(g)
146.4kJ • 1110Z- 1
+
Mg(g) ➔ Mg (g)+ e
+
1
737.7k/ · mOZ-
1
Mg (g) ➔ Mg2+ (g) +e
1450.6kJ · moZ- 1
1
Mg(s)+-O2 ➔ MgO(s)
2
-6Ql.2k/ • moZ-
1
Hmmgd§n
a) Tinh nang luqng rn:;i.ng lu&i:
l.7476x 6.022x 1023 mOZ- 1 X 2X (-2)x (-1.602x 10- 19
=
4X 3.}4X 8.854 x }Q - 12 C2•]-1 •m-l X 21Q x 10- 12 m
cf {l- Q.31x
}Q-IO
mJ
2}0X 10- m
12
::: -3943k] •moZ- 1
b)Xay d\rng chu trlnh Born-Haber d� tinh ai l\rc electron thu hai:
-601.2kJ •n10r 1 -(146.4+ 737.7+ 1450.6+ 249.2-141.8-3943)k/ •mor 1 + Y2
½ ::: 899.7 kJ •l110Z-
1
185
Mg( � -}o,(g)
146.4
Mg(g)
7377 j
J 498.4/2
O(g )
J
141.8
-3943
Mg (8) ◊-(g>
l4S0.6 J
�
jY
-'
Mg2•(g)-+-0:-( g)----
186
Bai 102 - Nang hrQ'llg m�ng lll'6i
1)
sip x�p tr�,t tl,1' dQ l&n nang ltrQ'ng m�ng tinh thB Clla cac ch§t sau day va giai thfch:
CaO, NaBr, SrO, ScN, KBr, BaO
Bi�t cac ch§t tren dSu thuoc kiBu du true tinh thS NaCl.
2) Giai thfch S1,1' tang dAn nhi�t do n6ng chay va nhi�t do soi Clla cac chftt sau day:
NaF
MgF2
AlF3
Nhi�t do n6ng chay ( °C)
992
1263
1270
Nhi�t do soi (°C)
1704
2300
1270 (thang hoa)
Hmrng d�n
1) Cong thfrc nang lm;mg m:;ing hr&i tinh thB:
U :::
AN A
2
e
4n60
(1
_ _!_) Z+Zx
m
,�
Do cac kim lo�i trong cau hoi dSu thuQc, h�.ng s6 Madenlung A la gi6ng nhau va h� s6 Born
+ khong qua khac bi�t, do do nang ltrQ'Ilg m;;mg luoi cht1 y�u ph1,1 thuoc vao
2
2
1�
Chia cac chfit nay thanh 3 nh6m: (1) ScN ; (2) CaO, SrO, BaO ; (3) NaBr, KBr o
Trong nh6m thtr hai, t:J.i s6 di�n tfch cfia ca.c ion fun va duang trong 3 oxide d�u gi6ng nhau,
nlnmg ban kinh tang 1:t'r Ca2+ d�n Ba2+ , do d6 do dai lien k�t tang hr CaO d�n BaO, do d6 gia tii
nang hrqng m:;ing hr&i giam tl'r CaO d�n BaO. TuO'llg nr v&i nh6m thu ba. S o v&i CaO th'i ScN c6
dQ dai Lien k�t l&n han, nl1tmg S\1' chenh l�ch khong l&n hiy nhien ti·ong ScN c6 di�n tich cac ion
16n hem nhiSu, do d6 nang lm;mg m�ng hr&i I&n hon Cao. So sanh Bao va NaBr thi chiit d�u c6
di�n tlch l&n han va do dai lien k�t nh6 han, do d6 nang hrqng m:;ing lu&i 1611 hO'll chiit sau. Do
d6:
ScN >CaO >SrO > BaO >NaBr> KBr
2) Hai hqp ch§t NaF va MgF2 dSu la ion, ti·ong d6 u ml Clla MgF2 l&n hem nen nhi�t do n6ng chay
se cao han. V 6i AlF3 nhi�t do n6ng chay l&n nh�t b&i 116 t�o thanh tu cac bat di�n ALF63- ch�t
khit. Nhm1g khi dun n6ng thi cac bat di�n nay bi pha vo dfu1 d�n s1,r t�o thanh cac hO'i phan tir
AlF3 & tr:;ing thai hO'i, chinh vi th� khi n6ng chay cfmg la luc AlF3 thang hoa.
187
Bai 103 - Nang hrQ'llg m�ng lll'6i
Di�m n6ng chay cua fluroride eua eae nguyen t6 elm ki ba tang d§.n theo ehi�u tl'r trai sang phai
r6i dot ngot giam m:;i.nh & SiF4 (xem bang du6i), sau d6 l� tang ch�m. Hay phan tich hi�n tm;mg
nay tren quan di�m d.u true.
Hc;rp ch�t
Pf;
NaF
Nhi�t do
n6ng ehay 993
; OC
1261
1291
-90
-83
-50.5
Hmmgdiin
NaF va MgF2 d�u la cac tinh th@ ion di@n hlnh. M�e du trong tinh th@ AlF3, kieh tlm&e ciia Al3+
nho hO'n va c6 mot ml'.tc do phan qre ion nh§t dinh nhung ch�t nay v§n thuoe k i�u tinh th@ ion.
Do cac ion fun va du011g trong tinh th� e6 hi�u img finh di�n m�nh, do d6 3 tinh th� nay e6 nhi�t
do n6ng chay eao nh§t. Tuy 3 tinh th@ ion nay e6 ki@u eftu true khae nhau, hfulg s6 Madelung
khac nhau nbnwg y8u t6 chinh anh lm&ng d8n nang hrc;rng m:;i.ng lu&i v§n la tri s6 di�n tfch ion va
do dai lien k8t. Tl'r NaF d8n AIF3, tri s6 di�n tich tang d§n con ban kfnh cation giam dful, do d6
nang hrc;rng m<,'lng luoi tang d§n, dful d8n nhi�t do soi tang d§n.
Do di�n tich ion du011g ti8p t11c tang va ban kinh ti�p tµe giam nen kha nang phan Cl,tC h6a ti8p
t1_1c tang len, dful dSn Sl,t thay d6i ban ehftt lien kSt va cftu true cac hop ehftt. Cac fluo1ide, bit d�u
tt'r SiF4, khong con la hc;rp ch§t ion. Cac nguyen tt"r duc;rc lien k�t v&i nhau b&i lien k�t cong h6a
tri d@ t:;i.o thanh phan tir, va cac phan tu kBt hc;rp v&i nhau b&i 11,rc van der Waals. Do hrc van der
Waals ySu hO'Il lien kBt ion nhi�u nen nhi�t do n6ng ehay eua ca.e fluo1ide nay d(>t ng(>t giam
m:;i.nh. Tt'r SiF4 dBn SF6 thl nhi�t do n6ng ehay tang d§n, b&i s1,r tang hrc lien phan tfr (eht1 y8u la
h,rc phan tan.)
188
Bai 110 - Cfiu true tinh th� ion
Nam 1929, nJ1a hoa hc;,c ki�t xu§t ngm:ri My Linus Pauling da c6ng b6 5 guy tic d� xac di11h d.u
true cua cac tinh th� ion:
l) khoang each ng�n nh§t gifra cac ion duqc xac dinh b&i t6ng ban kinh ion, trong khi d6 s6
ph6i 1Ii thi xac dinh d\ta vao ti l� cua chung;
2) t6ng di�n tfch ci'.la cation quanh m6i anion b�ng di�n tfch ciia anion;
3) d9 b�n ci'.la c§u true giam dang k� b&i S\t c6 m�t cac c� va m�t k8 c�n trong da di�n
ph6i trf (CP);
4) cac cation nho va c6 hoa tri l&n c6 XU lm&ng kh6ng chung anion;
5) s6 CP v&i c§u tn'.lc khac nhau c6 XU hu&ng d:;it gia tri C\tC ti8u.
Nhi�u hqp chiit hrong nguyen t6 d�ng A+ B- t:;to ra cac m:;ing tinh th8 v&i c§u true I, IT (d9 b8n
cua cac hQ'JJ ch§t trong cac d�ng I, II phu hqp v&i If thuyBt Pauling).
II
0 -KarnoH
•-aH�CH
Tfnh khdi lu()'Ilg rieng Clla CsF. D8 tinh duqc, hay xac dinh:
a) cac thong s6 m:;ing a(I) va a(II), bi�t ban kfnh ion dia cac cation va anfon;
b) s6 phan ur trong 6 m:;ing C(Y SO' cita cilu true I, II.
c) xac dinh biBu tht'.rc tfnh khdi luQ'ng rieng ciia cesium fluoride v&i cac cilu true I, II (vi�t kBt
qua theo d011 vi kg/m3 ).
Sir d\1□g cac gia tri sau: R(F-) = 1.33 A; R(Cs +) = 1.67 A; 1 A = 10- 10 m; M(CsF) = 0.1519
kg/mol; NA= 6.022 · 1023 moi- 1.
189
HU'(mgdiin
a) Theo quy ffi.c (1), hting s6 m�g cila c§u 1rl'.1c I la a(I) = R+ + R-
V6i mi;ing du true II, khoang each ngful nh§t giita cac cation va anion tn.\ng v6i ducmg cheo l�p
phmmg, nglua la:
a(Il)
✓3 = 2R +2R_
a(II) =
f
2
+
(R+ + R_)
✓3
� I1 0
A Illl;l.llg: v. = ( R+ +R_ )3 ; Yn = -8 ( R+ + R_ )3
TheJ. ttc
9
b) Xet c§u true Il: cation nfun hoan toan ben trong 6 mc;1ng, do d6 ZAB = 1. Theo quy tic (2), di�n
tfcb cation (b�ng + 1) pbai duqc bu trir b&i cac anion n'r moi tntcmg ph6i trf g:in nh§t, nglua la bm
8 anion, mang di�n tfch -1.
c) Bi�u thitc tinh (i = I, II):
d. z; MA
B
=
N•V
I
n
I
190
Bai 104 - Tinh th� NaH
NaH c6 diu true tinh th� k.i�u NaCl. Bi�t r�ng h�ng s6 o m�ng l�.p plmO'ng a = 488 pm va ban
kfnh Na+ la I 02 pm, tfnh ban kinh H-. Danh gia tinh base ciia cita H- qua plmong trinl1:
NaH + H2 0 ➔ H 2 t +NaOH
Hll'61tg d§n
Do NaH c6 c�u true ki�u NaCl nen ban kfnh ciia Na+ va ff va h�g s6 m�mg c6 m6i lien h� nlm
sau:
2(rNa +r_)=a
H
+
I
I
rH_ =-a- rNa ,. = -x488pm-102pm= 142pm
2
2
Thuy phan NaH thanh H2 va NaOH cho th�y r�ng kha nang nh� proton cu.a H- m� hon OH-,
c6 nghla rfulg NaH c6 tlnh base m�nh hon NaOH.
191
Bai 105 - Tinh th� ion
K�t qua phan tfch nhi�u x� tia X cho thfiy m9t tinh th� ion thu9c ki�u tinh th� l�p plumng v&i
h�ng s6 m:;111g a= 403.1 pm. Vi hi cac dinh trong o m:;ing bi chi�m b&i cac ion Ti4+, vi tri' tam
kh6i bi chi�m b&i Ba2+, con vi tri' cac tam m�t la cac 02-.
a) Xac dinh cong thuc h6a h9c ciia tinh th�.
b) Xac dinh s6 ph6i tri' v&i oxygen cua Ti4+ va Ba2+.
c) Tfnh ban kfnh hai cation, bi�t ban ki'nh 02- la 140 pm.
Hll'61tg d�n
a) S6 ion Ba2+ la 1
S6 ion Ti4+ la:
l
8x-=l
S6 ion 02 -1a
12x _!_ = 3
Cong thirc hQ'p chfit la BaTi0 3
b) S6 ph6i trf v&i oxygen ciia Ti4+ va Ba2+ l§n hrQ't la 6 va I 2.
c)
1
2
1
2
r71..J+ = -a-r,V..z_ = -x403.lpm-140pm= 61.6pm
✓
r8,;+ = _!_ 2a- rd_ = _!_ ✓2 x403. I pm- J40pm= J45pm
2
2
192
Bai 111 - Cfiu true tinh th� ion
Mu6i lithium chloride LiCl k�t tinh theo m�ng l�p plurong tam di�n. 6 m�ng c<:1 s6' c6 dQ dai m6i
c:;mh la 5.14·10- 10 m. Gia thi�t ion Li+ nh6 d�n mire c6 th� xay ra ti�p xuc anion - anion va ion
Li+ duqc x�p khft vao khe giua cac ion CJ-. Hay tinh dQ dai ban kfnh ctia m6i ion Lt va Ct trong
m�g tinh th� theo pm.
Hmrngd§n
M6i lol;li ion t�o ra m(it m�g b;ip plnrong tam m�t, hai m�ng d6 16ng va o nhau, khoang each gitra
hai m�ng la � va tam giac t�o th anh b6'i hai c�nh g6c vuong a, a con c�h huy�n la dm:mg cheo
d, khi d6:
2
d2 = 2a2 ⇒ d = a
✓2
a✓2
d = 4r(Ci-) ⇒ r(CJ-) = - = 182 pm
4
+
Xet m(H c�h a: a = 2r(Li ) + 2r(Ci-) ⇒ r(Ci-) = 75 pm
193
Bai 106 - Cfiu true tinh th� ion
Khdi htQ'llg rieng Clla barium vao khoang 3.65 g/cm 3 va ban kinh nguyen tit cua 116 la 217.4 pm.
a) Cho bi�t d.u true tinh th� barium, bi�t 116 k�t tinh & mot trong cac kj�u m:;ing l�p phuong.
b) Cho bi�t s6 phdi trf cf1a Ba2+ va 02- a-ong BaO, bi�t n6 k�t tinh theo ki�u m:;ing NaCl.
c) Barium peroxide cung k@t tinh the o ki�u m:;ing nay tuy nhjen c6 mQt chi�u hcri l�ch han
so v6'i ki�u o m.,1ng li tu&ng. K�t qua la xu�t hi�n ki8u 6 m<;lllg tu di�n nlm calcium
carbide. Giai thfch t<;li sao l<;li nhu v�y
194
HU'(mgdiin
m n.137
1-i.. t eo cong
.,.. dUQ'c tum
a ) Kh;,,01. l m:mg neng
thuc:
h
' p ;::; - ;:::
3
A
V
NA .a
Do Ba c6 m�ng tinh th� Hip plmO'ng nen ta se c6 bang sau:
L�p plumng don gian
L�.p plurong ram kh6i
✓3 =502.1· 10- cm
L�p plurm1g tam m{lt
Chi�u dai c� 0 2r = 434.8· lo- 10cm
m:;1ng CO' s&
4r/
So nguyen tir Ba c6
trong mot o m:;1ng
2
4
3.60 g/cm3
3.92 g/cm3
l
K8t qua tfnh kh6i 2.77 g/cm3
ltrqng rieng
10
2 .fi_ r = 614.9· 10- 10cm
?
0\ra vao ket qua ta thay Ba c6 m:;1ng tmh the 1ip pluwng tam kh61.
b) S6 ph6i tri d8u la 6.
c) Trong barium peroxide thl anion 0 2- se bi thay th8 b�ng oi2- dinh lnr&ng thfulg nen n6 se
duqc s�p x8p song song theo m9t trµc, di�u nay lam cho du true l�p phuong bi l�ch mQt
each dang k8 nlur hinh ve .
195
Bai 107 - Tinh th� oxide h6n hQ'p
Khi dw1 n6ng h6n hqp bismuth va germanium trong oxygen khong khf & 900 °C thu duQ'c hai hqp
ch�t A va B d�u la cac oxide h6n hqp cila hai kim lo:;i.i tren (cong thirc t6ng quat c6 d:;i.ng
xBi2O 3.yGeO2). Cac k�t qua nghien ciru diu true cho th�y trong A h�g s6 m:,ing a= 10 14.Spm
va kh6i luqng rieng d= 4.62 g/cm 3, m(>t 6 m:;ing ca s& ct1a A chira hai nguyen tu Ge. Con cac k�t
qua tuong 1:l,r v&i B nlur sau: a = 1059.4 pm va d = 3.47 g cm-3, va trong 6 m:;i.ng ct1a B thl Ge t6n
t:,ti & d:;i.ng (GeQ4)4-. Hay d� nghi cong thirc cirn A va B du&i d:,tng h6n hqp hai oxit. Bi�t Mai =
209.0; MGe = 72.61 va Mo= 16.00.
Hmmgd�n
Th8 tfch 6 m,;1ng h·ong A = (10.145·10- 8)3 = l.044· 10-21 cm 3
Nhu v�y kh6i luQ'Ilg nguyen tir ctia B = 1.044· 10- 2 1 · 4,62 · 6.02·10 23 = 2904 g 11101-1
Do trong 6 rnc;1ng ca s& cila A c6 2 nguyen tir Ge nen y = 2. Tl'r d6 v&i cong thirc t6ng quat
xBiiO 3.yGeO2 c6 th� tinh duQ'c x= 6. Hay cong th(rc ciia A c6 dc;lllg 6 BiiO3.2GeO2.
Tuong 1:\r tinh duqc Ms = 2485 g mo1·1
Theo d�u bai th} Ge t6n t<;li trong 6 m:;ing & d:;ing t(r di�n (GeO4)4-. TI1eo dinh lu�t bao toan di�n
tfch th'i cu ba tl'.r di�n (GeQ4)4- dn 4 ion Bi3+. Nlur v�y cong th(rc cila oxide c6 th� tri8n khai &
d:,ing [Bi4(GeO4)3h . V&i Ms =2485 g mo1-1 c6 th8 tinh duQ'c x = 2. T(rc B c6 CTPT BisG�O24
hay 4BhO 3 .6GeO2.
196
Bai 108 - Tinh th� nickel oxide
NiO c6 d .u true tinh th� ki�u NaCl, va. khi dun n6ng trong oxygen thi mot phiin Ni2+ se bi oxid
h6a thanh Ni3+ , t:;i.o thanh NixO (x < 1). C6 mot lm;mg Nix O c6 kh6i ltrQ'ng rieng 6.47 gram cm-3.
Chi s6 nhi�u x:,1. & m�t 111 ci1a 6 m:;tng l�p plnrong lae= 18.71° (sine= 0.3208) duQ'c do b6i
plnr0'11g phap nhi�u x:;i. b9t tia X v&i bu&c song A= 154 pm. Kh6i hrQ'ng nguyen tfr orang d6i ciia
Ni la 58.70.
a) Tinh cac h�ng s6 m:;i.ng Clla Nix O.
b) Tinh gia tri x vi�t cong thirc h6a hQc cua NixO, chi ro s6 oxid h6a cua Ni.
c) Trong cac tinh th� Nix O, d:;i.ng silp x�p cua 02 - la gl? Ni se chj�m nhung h6c nao? Ti 1� bi
chi@m la bao nhieu?
d) Tinh khoang each ngiln nh�t gifra Ni-Ni trong tinh th� NixO.
Hmrng diin
H�ngs6 m:;tng l�p phmmg ci1a NixO la:
a=
✓
h 2 +k 2 +l 2 = lS4pm '-h2 +12 +I 2 = 416pm
A.
2sin0
2sinl8.71 °
a) Do tinh th� NixO c6 ki�u du true NaCl, kh6i lm;mg mol se la:
1
3
M=-Da NA
4
3
= ¾x6.74g•cm-' x( 416x Hr' 0 cm) x6.022xl0 23 mor'
= 70. lg•mor'
Kh6i luqng mol ci1a NixO c6 th� bi�u di�n la:
M= 58.?0g•mor' xx+ 16.00g•mor' =70. lg•mor'
V�y x = 0.92
Gia sfr r�ngs6 mol Ni2+ trong 0.92 mot nickel la y, s6 mol Ni3 + se la (0.92 - y). Gia tri nay c6 th�
dUQ'C xac dinh b&i can b�ng di�n tfch:
2y+3(0.92- y)= 2
y=0.76
0.92- y = 0.16
197
c) Tinh theNi�;6Ni��6 O c6 du true kieu NaCl va s1,r s�p xSp 02 - hrong u,r nlnr c1- t:rong tinh the
NaCl, nghia la l�p plmO'ng tam kh6i. Cac nickel ion chi�m cac h6c tfr di�n t:;to thanh b&i 02 -. Ti
1� chiSm la 92 %.
d) Cac nkkel ion phan b6 & vi trf tam kh6i va trung diem cac qmh cua 6 m:;ing l�p plnrong.
Kboang each Ni-Ni ng� nh§.t la khoang each gifra 2 nickel ion & tam kh6i va & gifra b�t kl qmb
nao:
]._.Ja2 +a2 = ✓2 a= ✓2 x416prn = 294pm
2
2
2
Khoang each Ni-Ni ng� nh§.t cfmg bing khoang each gifra hai nickel ion & tam cua hai cl;lllh c�t
nhau trong cung mot m�t:
198
Bai 109 - Tinh th� iron oxide
Iron oxide FexO c6 ci:mg ki�u c�u true v&i sodium chloride. Trong die tinh thS th1,tc t� x < 1 do
khi�m khuy�t tinh thS. C6 m9t hrqng iron oxide c6 kh6i luqng rieng la 5 .171 gram cm-3 va chi s6
nhi�u X<;l & m�it 200 cu.a 6 m,;1ng l�p plmang tam di�n la 0 = 9.56 (sin 0 = 0.3208) dtrQ'C do b&i tia
Mo K a,').,,= 71.07. Cho bi�t kh6i luqng mol tmmg d6i cua silt la 55.85.
a) Tfnh h�ng s6 o m,;1ng tinh thS cua Fex O.
b) Tfnh gia tri x vi�t cong thl'.rc h6a hQc cu.a Fe1.0, chi ro s6 oxid h6a cua Fe.
199
HU'(mgd�n
a)
a=
✓
A.
h2 +k 2 +! 2 = ?l.O?pm .J22 +O2 +O2 =427.8pm
2sin0
2sin 9.56°
f
M = � a3 DNA =: x (427.8x 10- 10 cm x 5.7 lg•cm-3 x 6.O22x 10 23 mor'
= 67.35g•mor'
M = 55.85g•mor 1 xx+I6.00g•mor' = 67.35g•mor'
X= 0.92
Gia sir r�ng s6 mot Fe2+ trong 0.92 mot nickel la y, s6 mot Fe3+ se la (0.92 - y). Gia tii nay c6 th�
dm;rc xac dinh b&i can b�ng di�u tich:
2y+3(0.92- y)= 2
y:::0.76
0.92-y:::0.16
200