Chemistry 122 [Tyvoll]
Summer 2007
Chapter 8 Homework Solutions
26. (a) the subshell that fills after [Ar] is 4s ... there is no 2d subshell since, when n= 2,
the maximum value of l is 2-1 = 1 (a p-subshell) .. rules for quantum numbers n
and l
(b) the subshell that fills after [Ar]4s2 is 3d ...Pauli exclusion principle and Aufbau
rules
(c) the subshell that fills after [Kr]4d105s2 is 5p ... 4f fills after 6s .. Aufbau filling
rules
28. (a) Ar
(b) Al
(c) Ne
(d) B
(e) Ca
(f) N
(g) Cl
(h) S
(i) Zn
1s22s22p63s23p6
1s22s22p63s23p1
1s22s22p6
1s22s22p1
1s22s22p63s23p64s2
1s22s22p3
1s22s22p63s23p5
1s22s22p63s23p4
1s22s22p63s23p63d104s2
30. (a) Al
(b) Ga
(c) Zr
(d) I
(e) As
(f) Ba
[Ne]3s23p1
[Ar]3d104s24p1
[Kr]4d25s2
[Kr]4d105s25p5
[Ar]3d104s24p3
[Xe]6s2
32. (a) C
(b) O
(c) K
(d) Al
(e) S
(f) Mg
(
(
(
(
(
(
1s
(
(
(
(
(
(
2s
(
(((
(((
(((
(((
2p
((((
(
(( (
3s 3p 4s
36. (a) Ga3+ [Ar] ( ( ( ( ( (3d6)
(b) V3+ [Ar] (3d2)
(c) I[Xe]
(d) Sb3+ [Kr] ( ( ( ( ( ( (4d65s2)
42. (a) As
(b) Tl
(c) Y
[Ar]4s23d104p3
[Xe]6s24f145d106p1
[Kr]5s24d1
[Kr]4d105s25px15py1
[Xe]4f145d46s2
[Xe] 4f145d10
[Kr] 2s22px22py22pz2
[Xe] 4f145d106s26px26py26pz2
46. (a)
(b)
(c)
(d)
(e)
Sn
W
Tl3+
O2Rn
50. (a)
(b)
(c)
(d)
C<Ca
Mg2+<Fe2+
F<Si
Zn2+<Ca2+
2 unpaired e-; paramagnetic
4 unpaired e-; paramagnetic
0 unpaired e-; diamagnetic
0 unpaired e-; diamagnetic
0 unpaired e-; diamagnetic
Ca is two periods below C (has two more shells of e-)
Fe is one period below Mg (has one more shell of e-)
Si is one period below F (has one more shell of e-)
Zn2+ is to the right of Ca2+
52. (a) S<Se<Ga<In (S has one less shell than Se/Ga; Se to the right of Ga; Ga one less
shell than In)
(b) In3+< Sr2+< Rb+< Rb
58. (a) Ca to the left of As (I. E. for Ca larger than for As); for I.E. increase
down<increase to right, so I. E. for Ca larger than for Na (Na<Ca<As)
(b) Sn to the left of and below As; As to the left of and below S (Sn<As<S)
(c) Kr noble gas with high I.E.; Ba to the left, below Sc and about equal to Ca, to
the left of Zn; Zn to the left and below Al; Br farther to right than below Al,
so we predict: Ba<Sc<Zn<Al<Br<Kr. The actual is slightly different:
Ba<Al<Sc<Zn<Br<Kr, since Zn is transition element and Al lower because of
filled subshell.
62. For Groups 2A and 8A, the additional electron would have to go into a higher
energy subshell (2A) or shell (8A). Result is a positive electron affinity because the
anion formed is not stable.
72. (a) 2 K(s) + 2 H2O(l) 2 K+(aq) + 2 OH1-(aq) + H2(g)
(b) Ca(s) + 2 H+(aq) Ca2+(aq) + H2(g)
(c) Be(s) + H2O(l) No Reaction (no rxn)
74. (a) SO3(g) + 2 KOH(aq) K2SO4(aq) + H2O(l)
(b) Al2O3(s) + 6 H+(aq) 2 Al3+(aq) + 3 H2O(l)
(c) CaO(s) + H2O(l) Ca(OH)2(aq)