CHEM 101
CHAPTER 8 PRACTICE PROBLEMS
8.12
(a)
ml = 0, p shaped sublevel, 2 maximum electrons (1 orbital)
(b)
5p (ml = -1, 0, +1), 6 maximum electrons (3 orbitals)
(c)
l = 3, f shaped sublevel, 14 maximum electrons (7 orbitals)
8.14
(a)
2s (1 orbital), 2 maximum electrons
(b)
l = 2, d shape (5 orbitals), 10 maximum electrons
(c)
6d (5 orbitals), 10 maximum electrons
8.22
(a)
n = 2, l = 0, ml = 0, ms = +1/2
(b)
n = 4, l = 1, ml = +1, ms = -1/2
(c)
n = 6, l = 0, ml = 0, ms = +1/2
(d)
n = 2, l = 1, ml = -1, ms = +1/2
8.24
(a)
Br – 1s22s22p63s23p64s23d104p5
(b)
Mg – 1s22s22p63s2
(c)
Se – 1s22s22p63s23p64s23d104p4
8.26
(a)
S – 1s22s22p63s23p4
(b)
Kr – 1s22s22p63s23p64s23d104p6
(c)
Cs – 1s22s22p63s23p64s23d104p65s24d105p66s1
8.28
(a)
Ba: [Xe]6s2, [Xe] ___
6s
(b)
Co: [Ar] 4s23d7, [Ar] ___ ___ ___ ___ ___ ___
4s
3d
(c)
Ag: [Kr] 5s14d10, [Kr] ___ ___ ___ ___ ___ ___
5s
4d
8.30
(a)
Ga: [Ar] 4s23d104p1, [Ar] ___ ___ ___ ___ ___ ___ ___ ___ ___
4s
3d
4p
(b)
Zn: [Ar] 4s23d10, [Ar] ___ ___ ___ ___ ___ ___
4s
3d
(c)
Sc: [Ar] 4s23d1, [Ar] ___ ___ ___ ___ ___ ___
4s
3d
8.32
(a)
[Kr] ___ ___ ___ ___ ___ ___, Cd, 2B(12), Period 5
5s
4d
(b)
[Ar] ___ ___ ___ ___ ___ ___, Ni, 8B(10), Period 4
4s
3d
8.34
(a)
[Ar] ___ ___ ___ ___ ___ ___, Mn, 7B(7), Period 4
4s
3d
(b)
[Kr] ___ ___ ___ ___ ___ ___, Zr, 4B(4), Period 5
5s
4d
8.36
(a)
[Kr] 5s14d4, Nb, 5B(5)
(b)
[He] 2s22p3, N, 5A(15)
8.38
(a)
Br – [Ar] 4s23d104p5
 28 inner electrons
 7 outer electrons
 7 valence electrons
(b)
Cs – [Xe] 6s1
 54 inner electrons
 1 outer electron
 1 valence electron
(c)
Cr – [Ar] 4s13d5
 18 inner electrons
 1 outer electrons
 6 valence electrons
(d)
Sr – [Kr] 5s2
 36 inner electrons
 2 outer electrons
 2 valence electrons
(e)
F – [He] 2s22p5
 2 inner electrons
 7 outer electrons
 7 valence electrons
8.40
(a)
Se (O, S, Te, Po)
(b)
Hf (Ti, Zr, Rf)
(c)
Mn (Tc, Re, Bh)
8.42
(a)
Ge (C, Si, Sn, Pb)
(b)
Co (Rh, Ir, Mt)
(c)
Tc (Mn, Re, Bh)
8.54
(a)
Pb > Sn > Ge (atomic size increases down a group)
(b)
Sr > Sn > Te (atomic size decreases across a period)
(c)
Na > F > Ne (Na is far left side and F is to the left of Ne in the
same period)
(d)
Na > Mg > Be (Na is farthest down and left. Mg is Be in the
same group)
8.56
(a)
Li > Na > K (decrease down a group)
(b)
F > C > Be
(c)
(increase as you go across a period)
Ar > Cl > Na (increase as you go across a period)
(d)
Cl > Br > Se [Cl is above Br in the same family (decreases
down a family) and Br is to the right of Se (increases across a
period)]
8.58
(The element is magnesium) 1s22s22p63s2 [the big jump in IE is
taking the third electron]
8.60
(a)
Al (taking three electrons from Na and Mg would mean taking
electrons from stable electron arrangements)
(b)
Sc (taking three electrons from K and Ca would mean taking
electrons from stable electron arrangements)
(c)
Al (taking three electrons from Li and B would mean taking
electrons from stable electron arrangements)
8.70
(a)
S (it is farther left in the same period)
(b)
In (it is farther down in the same group)
(c)
As (it is farther left in the same period)
8.72
(a)
Rn (it is farther to the right in the same period)
(b)
Te (it is farther to the right in the same period)
(c)
Se (it is farther to the right in the same period)
8.76
(a)
Rb+ (because it is in Group 1A) 1s22s22p63s23p64s23d104p6
(b)
N3- (because it is in Group 5A) 1s22s22p63s23p6
(c)
Br- (because it is in Group 7A) 1s22s22p63s23p64s23d104p6
8.78
(a)
P3- (because it is in Group 5A) 1s22s22p63s23p6
(b)
Mg2+ (because it is in Group 2A) 1s22s22p6
(c)
Se2- (because it is in Group 6A) 1s22s22p63s23p64s23d104p6
8.80
(a)
2 unpaired electrons (carbon for example) ___ ___ ___ ___
2s
2p
(b)
1 unpaired electron (fluorine for example) ___ ___ ___ ___
2s
2p
(c)
1 unpaired electron (lithium for example) ___ ___
1s 2s
(d)
2 unpaired electrons (oxygen for example) ___ ___ ___ ___
2s
2p
8.82
(a)
[Ar] 3d2 (lost its 4s2 electrons when it formed a +2 ion)
___ ___ ___ ___ ___
3d
It is paramagnetic because it has unpaired electrons
(b)
[Ar] 3d10 (lost its 4s2 electrons when it formed a +2 ion)
___ ___ ___ ___ ___
3d
It is NOT paramagnetic (all electrons are paired)
(c)
[Ar] (Lost its 4s2 electrons when it formed a +2 ion)
[Ar] is a noble gas. It has a stable electron arrangement with all
paired electrons.
It is NOT paramagnetic (all electrons are paired)
(d)
[Kr] 5s24d10 (lost its 5p2 electrons when it formed a +2 ion)
___ ___ ___ ___ ___ ___
5s
4d
It is NOT paramagnetic (all electrons are paired)
8.88
(a)
Se2- > S2- > O2- (they are all the same charge and in the same
group… ion size increases down a group)
(b)
Te2- > I- > Cs+ (the most negative ion will be the largest and the
most positive ion will be the smallest)
(c)
Cs+ > Ba2+ > Sr2+ (Cs+ is larger than Ba2+ because it is less
positive and Ba2+ is larger than Sr2+ because it is farther down in
the same group)