No. of Printed Pages : 16
CHE-01
BACHELOR OF SCIENCE (B.Sc.)
Term-End Examination
June, 2012
Cyr
CHEMISTRY
CHE-01 : ATOMS AND MOLECULES
Maximum Marks : 25
Time : 1 hour
B.Sc. EXAMINATION
CHE-01 : ATOMS AND MOLECULES
AND
CHE-02 : INORGANIC CHEMISTRY
Instructions :
(i) Students registered for both CHE-01 and CHE-02
courses should answer both the question papers in
two separate answer books entering their
enrolment number, course code and course title
clearly on both the answer books.
(ii) Students who have registered for CHE-01 or
CHE-02 should answer the relevant question
paper after entering their enrolment number,
course code and course title on the answer book.
Note : Answer all the five questions.
CHE-01
1
P.T.O.
Use the following data whenever required :
Planck's Constant, h = 6.626 x 10 -34 J s
Velocity of light, c = 2.998 x 108 m s -1
1.
Answer any two parts :
(a)
Name two experimental observations which
could not be explained on the basis of
classical physics.
(b)
Amongst the following which is the
strongest bond and which is the weakest ?
C - H, C - C, C=C and C - C/
(c)
2.
Covalent radius of carbon increases,
decreases or remains constant with increase
of s-character in the different hybridized
states ?
Answer any two parts :
(a) Write the resonance structures of
(i)
(CH3)2 SO4
(ii)
FNO2
(b) Arrange the following ionic compounds in
order of increasing lattice energy KC1, KBr,
CaCl2 and MgCl2
Give reason for your order
(c) In the ground state of K (at. no =19) how
many electrons have m1 = +1 as one of their
quantum numbers ?
CHE-01
2
4
3.
Answer any two parts :
(a) The iodine bromide molecule (IBr) has a
bond length of 2.49 A° and a dipole moment
of 1.21 D. Calculate the effective charges
on the I and Br atoms in IBr in units of
electronic charge, e. (1D = 3.34 x 10 -3° C m,
electronic charge, e= 1.602 x 10 -19 C)
(b) Write the expression for vibrational energy
(Evib) and name the various terms used in
it. Explain the term, zero point energy.
(c) Calculate the number of a-particles and
13 particles emitted during the transformation
2
of a 23
90 Th nucleus to 2°8
82 Pb nucleus.
4.
Answer any two parts :
(a) A proton is accelerated to one - tenth the
velocity of light. Suppose its velocity can be
measured with a precision of ± 1%, what
must be the uncertainty in its position
(in nm) ? (mass of proton = 1.673 x 10 -27 kg)
(b) (i) Which has larger H - N - H bond
8
angles, NH3 or NH2 ? Give reason
for your answer.
(ii) The 1:C / 6 C ratio in the fossil of a
plant is 1/16th of that in a living plant.
How old is the fossil ?
(t y2 for C
14
6 = 5720 years)
CHE-01
3
P.T.O.
(c) Using M.O. theory predict the following
about NO+ and NO- ions.
(i) Which of them is paramagnetic
(ii) Which of them has longer nitrogenoxygen bond length ?
5.
Answer any one part :
(a) The shortest wave number absorption line
in the rotational spectrum of HC/ is at 20.70
-1.
cm
(i) Which are the two levels involved in
this transition ?
(ii) What is the value of the rotational
constant B for HC/ ?
(iii) Calculate the moment of inertia for
HC/.
(iv) Calculate the bond length of HC/
(in pm) (reduced mass of
HC/ = 1.627 x 10 27kg)
1/2
2
2
Which set of hybrid orbitals are used
by the central atom in AIC/4 - and
HCN
2
(ii) Calculate the number of photons of a
radiation with A= 560 nm which can
produce 198.6 J of energy.
2
(iii) Ti 3+ has one unpaired electron, what
is the value of its magnetic moment in
B.M. ?
1
(b) (i)
CHE-01
1/2
4
Tft.7-w1.-01
aqui t—Hoch (4'.71 11
it Ail TR-11-1T
2012
(1011
Tft:cl-W1.- ; 4 t HI klA 30
39
3ifETWUTT 3.7'W :
tWiel : 1 quei
25
TT* litk-Tr
1
:1174 - 01 : -111kt
3IT 317
R-4
1114-02 : 3T%-re5W
is
:
(i)
i,H )
WO/%1 F17.7-q.e.-01
Rlq
g cr)-17m77q-gy- drH 3.77T-37—M7T
dri1 SftiW3T7 31V'T 3 i
clIqqs17H (175
UnT Wc52107H Tri q197--q1Y7 C1C1471 I
X17
e.-01 z1T
fold ri4707
3T9# 3147 S1Y1Y
3FT7T 31 Tr cild219"
t1/ 2417H 7177 141917--q1Y7 RItIct7(
Yr??1-7
Va. :
CHE-01
qct,
dIV-
U217
719.17 rifW 31•?-1 . dri( g7fwk,i
5
P.T.O.
aTtw* r 3 1Tr
3TP-Ffw
cf, :
(h)= 6.626 x 10 -34 .1
Ychiqi ct) +i rd (c)= 2.998 x 108 m s -1
1. '7770-40 t 37R q'Irs-TR
(a) t whiff t T-44 qlr\TR, f
ITIFT*1-.k 3-TRTR -(4
(b)
Rgd
yrtuii+11
-14-11q1
-16
,k-ichr
al-f--7:11,31T4N 1,=4(1c14-131r{09TFT
T4--M-d7 31-14q
C—H, C C, C=C 31-{C—Ci
(c) rgrir 4.mur 3TaT-24T3
f- rr .qzrE
21-1f1:21-{
2.
ft--#0'11-11ff
(a)
,41(-11 t 1 t I (11 t
t?
d7R
q \TR
F-H-Irringcr -4. 31-fig
(i)
(b)
wr-47
s-fir
(CH3)2 SO4
fol7N7 :
(ii)
FNO2
AM* d)■
31
wi:r F-14-t ro d zerr--4
3Taft-era
KC/, KBr, CaCl2 and MgCl2
311T4
(c) K(
chwit
4taqi= 19)
q'lr\TR I
3-14T-21T
ii.(9q m1= 1 61411 ?
CHE-01
f*-a--4
3.
r;f2.67
t 31k 41r•TR :
31 (IBr) t 37411
2.49A°
(a) 3-1171W-9.
Ti 31T7,
aT fgv ampf 1.21 D t I IBr
e, Hlich 4 I 3-fOr TR171:13-ti 3mr-al 33r4T4
11-',3f7 I (1D = 3.34 x 10 3° Cm,
3-TOT, e = 1.602 x10 -19 C)
ffffti7 *7r
(Evib) t
(b)
r\TI
q•-e{
d,$)i
-5r-i*1
-- Fa 19.N.
s
s Pb
90 Th
(c)
4.
ictRcr
*R chuii
t4
LiRchoi Vf-A-R I
4(seli
r
8
ch.67VITIr1 drlt 41 z1 :
(a)
Tj ITM
t I 1T19. Fri 1,3i W-4 -± 1 % trfRIZ7T
ETT
ti cr) d r t I 71 T1 fRTfd
TITRT
(nm4) ?
4c414-111=1.673 x10 -27 kg)
(b)
(i)
NH3 342.74T NH2
(ii)
31N't1.1,1u1
31 siTR rc-K chRur
qlr,t
1-k Q-471411 164C / 11C 3T Ti
1/16 .41- tRiT 1
t?
kr3
6
,tro 51chIYI
f-*--(14 3Tfir*--d7
( 164 c4 t i ,= 5720alsi)
72
CHE-01
7
P.T.O.
(c)
5.
349 -waTT #1Ziff
NO + 31 NO
Fri
Figcr r
(i)
t?
(ii) -0 14 -4 f- 74 31N-T
31-r4.4
t?
/%7*
(a)
9-1-rri
671(
:
HC/ tTh. 14-4?,14 1-11-1c11-I 31-4VhfuT (_11 c1(41
WY-If 20.70 cm -1 117 t
(i)
(ii)
49111-1u1 1419
HCl t
dozii (-cItTIFTIt?
1/2
TIN cNI
1/2
(B)
FQ1
611?
o,c-vi
(iii) HC/ t frl s-TIS ccf 311EFI ti
47I
(iv)
HCl .4)1 31T-4N
( HCI
T
,ARcho-r
TITIT41
2
1ITT9
1.627 x 10 - 27kg t) I
(1)) (i) A/C14 - 3117 HCN t tk71 -7-{-149 t
4cr)tui
Mchlt
(ii) rarcnut
WlfA7 I
tali
gRairil
2
rarenoi 1 A = 560 nm t
2,T1 zq 198.6 J lqr
t
Ti 3+ 14 -crT 3-TOTM 4-4g17 t B.M. 1-111ch
31Pluf
CHE-01
2
8
qzrrTrr-ff dart?
1
CHE-02
BACHELOR OF SCIENCE (B.Sc.)
Term-End Examination
June, 2012
CHEMISTRY
CHE-02 : INORGANIC CHEMISTRY
Time : 2 hours
Maximum Marks : 50
Note : (i) Answer all the five questions.
(ii) All the questions carry equal marks.
1.
Answer any ten of the following :
lx10=10
(a) Amongst NaF, LiF and KF which one is the
most soluble in water and which one is the
least soluble ?
(b) Which one of the following alkali metal
carbonates is thermally the least stable ?
Li2CO3, Na2CO3, K2CO3, Cs2CO3
(c) Name the blocks into which the elements in
the periodic table have been divided.
(d) Which of the following elements has the
highest electron affinity ?
F, Cl, Br, I
(e) Write the electronic configuration of the
atom whose atomic number is 24.
(f) Write the IUPAC name and symbol of the
element having atomic number 105.
CHE-02
9
P.T.O.
(g)
List the factors which affect the atomic size
of the elements.
(h)
Which of the following elements has the
highest first ionisation energy ?
B,
C, N, 0
(i)
What is catenation ?
(i)
How many unpaired electrons are there in
[ Cr (CN)6 [3- complex ion ? (Atomic
number of Cr is 24).
(k) What is the most common oxidation state
of the transition elements of 3 d series ?
(1)
Give the coordination number and oxidation
number of cobalt in [ Co(NH3)5 Cl ]2 + ion.
(m) Give one example of a species which is
isoelectronic with 02- ion.
2.
(a) Define hydrogen bonding. What are the
types of H-bonding ? Give one example of
4
each type.
(b)
Draw and explain the structure of [ BeF4]2ion on the basis of valence Bond Theory.
4
(c)
Explain why there is a difference in the
bond angles of NH3 (107°) and PH3 (93°30').
2
OR
Explain the difference between white
phosphorus and red phosphorus.
CHE-02
10
3.
(a) How is diborane prepared ? Discuss the
nature of bonding in diborane.
(b)
4
Explain why trimethylamine is a stronger
Lewis base than trisilylamine.
OR
(c)
Explain why does SiC/4 undergo hydrolysis
whereas CCI4 does not.
4
Give reasons why Cu2 + ions are colored
2
and paramagnetic whereas Zn2 + ions are
colourless and diamagnetic. The atomic
numbers of Cu and Zn are 29 and 30,
respectively.
4.
(a) Write the chemical equations of reactions
4
involved in the extraction of copper from
the copper pyrites, CuFeS2.
(b) Answer any three of the following :
(i)
2x3=6
Why is the C/OC/ bond angle in C120
greater than the tetrahedral angle ?
(ii)
What are pseudohalogens and why
are they so called ? Give at least two
examples.
(iii) Complete any two of the following
equations :
XeF6 + Si02 -->
Xe03 + NaOH -->
2XeF6 + 6 H2O —>
(iv)
CHE-02
What are clathrates of noble gases ?
11
P.T.O.
5.
(a) Write the chemical formulae of any two of
1x2=2
the following :
(i)
Potassium hexafluorocobaltate (III)
(ii)
Potassium trichloromono-ethylene
platinate (II)
(iii) Tetraammine aqua bromochromium
(III) nitrate
(iv) Dichlorobis (ethylenediamine) cobalt
(II) monohydrate
(b)
Explain the hybridisation of cobalt and
shape of diamagnetic [ Co (CN)6 ]3complex ion on the basis of Valence Bond
Theory. (The atomic number of Co is 27).
4
(c)
What is lanthanide contraction ? Explain
its consequences.
4
CHE-02
12
(4 7111 i--110ch (*.71111)
t-1,11.1 ITTIATT
2012
.(flttri caoli
: al-W*1W
FITITT : 2 ETT4
37fETWTI7
Fr*
e:
v7-/1
:
50
dTv q7r3t
T12.77 31q-IT 31 FIRM. `/
1.
f44-4r1figd 4 A
--477:1A.
`31
1 x10 =10
(a)
NaF, LiF *KF 4 A AM chl-f TIT Traffw
ath 414 Tr
fq44 t?
(b)
f44-4 (M f (gcr ur{ trrg cni.pa 4 A cr> 4 err
TRI:24-rt t?
Li2CO3, Na2CO3, K2CO3, Cs2CO3
(c) 3ff
f-A-9-4
ITR-uft 4 Ic)
TrIri
(d)
t1
Fli-ironsicr 4 A
act
37:414-1 t ?
F, Cl, Br, I
(e) 1:171:r9 distil 24 girl
41-dT
7171:19
farrEr fra-R
CHE-02
13
P.T.O.
TR4IT131-1(ste-ii 105 c4
cicd
IUPAC 11:f 3T t
t-ftR I
3ff rt--*-1i&m.-11*
31-rwrT
*-Er-(Trrulaff*
cma t
12-14-11C1RA ci 14
3-ccid+-1
rcbq nor
32117 3-1719-ff a),3i
t?
B, C, N, 0
t?
-gzET
[ Cr (CN)6 ]3— ici3417f9. f-*--d4 391
1Trff
t? ( Cr SITU 4tsi124 t1)
3 d kit
491,Hur dccif
dq-ciefri 314Tqf
;i,44 3-TRiw
cid
Tft t ?
[ Co(NH3)5 C/ ]2 + 3TT3F 14 4 .W1
tit-if
q1F-TI
02- 3Trzrff
2.
(a)
141
Titrit
341-4%17 --1-1:1171751T q1Fr1 I H-3TT49-ff
fwd-4 mcni(
(b)
4
t?
31-r4tT -ftrzfu
3TrEN
34TNT-{ TR [ BeF4]2-
q11",,R 3th dkichr
r-
--1. 4R
CHE-02
'
14
.k.t{
g
dr)
4
(c) NH3 (107°) 3117 PH3 (93°30') t 31T-T -WIE4
2
t TcrE
ant4T
qdd
3.
(a)
it ltti 31I-{ ci (.1 !-111k-.41 kti
-1-$--qTci eht-f -51-*-17
3114q9
t?
3-f-dT TcrE
2
1-4--4Thi 4
4
q .ffT 4
4
fa-4-49T wlf-A7 I
17-ft
(b)
rociQi#9.
.) so4
T4TT vrt-w ail' ?
311T4T
TETI! -tr77
7-41
--CO4 f
(c)
SiC/4 1 \Tio 3Tc1131Eff cm) 6-1( t,
rt 31117eff
4
tI
Ruf A--dr-4- f Cu2+ 3TP:fi t4ilri 3 31-1-44-*--171
2
t, 7-4fw zn 2+ aTrzri TAR i 3th
5Ifa +1°h1q
I Cu 3th Zn
ITTIT9
i:ftwq
911 4-iqi: 29 3-th 30 t:I
4.
(a)
chr-it 414tNe,q CuFeS2, A cbit-It
ant
Pitch ui
31-fif-watrA -k km14'14>
4
chvii
f-of-u7
(b)
4--i ofigd
(i)
c5.6'69-qt apt
C120 4 cioci 3ff-44 chlut
:
2x3=6
°b1 q
ch ill A 31-14w
CHE-02
15
P.T.O.
.4z4
,414
q -9-rri
at{
azrr
3Trim:ft
f?
rs-TR
will.> uif T1 iv
(Ad
XeF6 +Si02
Xe03 + NaOH —>
2XeF6 + 6 H2O —>
5.
(a)
?
qzrr
(iv)
Th-fuR :
1x2=2
F-14--irringct -414 )%---477). tR-1141F-Ich
(i)
t-nN114 #R11:13121 ch)011c- e.
(ii)
LnN1144
lAt4Z
(iii) -4A+4-11-1 -crdziT 91)41)str4-iii-I (III)
:1t9)
(iv) 51c4cilUesiq (7P-1-1
~nl clird (II) 41-lit qe.
(b)
sYlchclf 31T4N rid
4
3748 tr{ ct)
4chtui 311T ;4R-litsich14 [ Co (CN)6
31FT9.
- 7 I Co
tRifrol
311-0
81c4 kui
d(ll 27 fl
(c)
t 3117
449T7 Tf-fqi qzrr
?
CHE-02
16
4zif -5111Td
4