Geology Reference
In-Depth Information
Therefore
6.4 (a) Rewrite Moseley's Law in the linear form:
aa a
=
×
K
HCO
+
H CO
2
3
3
506
.
6 4
.
=
10
×
10
1
2
(
) =−
1
2
1
2
kZ k σ
i.. ymxc
1
11 46
.
=
10
=+
10 5.
Therefore pH = 5.73
This is the pH value for pre-industrial rainwater.
The values for 1960 and 2012 are 5.71 and 5.66, a
pH change of - 0.05.
a H CO
=
=
/ ( ) and plot against
Z. Points fall on a straight line if the equation
holds.
1
2
For each point calculate 1
+
3
= (
) (
1
2
)
1
2
1561 1830
47 39
/. /.
k 2
=
gradient
1
2
=
0 00297
.
pm
Chapter 5
1
2
(
)
1
2
/k /λ
For yttrium (Y), for example, σ= −
σ= −
Z 11
0 1098
0 00296
.
5.1 2p, 3 s, 4f, 5d
5.2
39
.
6 C
1s 2 2s 2 2p 2
.
(b) Read off graph at Z = 43:
= 2 022
11 Na
1s 2 2s 2 2p 6 3s 1 or [Ne]3 s 1
13 Al
[Ne]3s 2 3p 1
17 Cl
[Ne]3s 2 3p 5
1
2
(
)
1
2
(
) =
.
Therefore λ = 67.6 pm = 0.676 × 10 −10 m
1
/
λ
0 1216
pm
18 Ar
[Ne]3s 2 3p 6 = [Ar]
26 Fe
[Ar]4s 2 3d 6
E v c
q
==
λ
4 135 10 2 997 10
0 676 10
/
(
)
(
)
.
×
15
.
×
8
1
eV sms
m
Chapter 6
=
10
.
×
=
183
30
eV
=
18 33
.
keV
6.1 The Pauli principle dictates that each orbital can
hold no more than two electrons:
Chapter 7
Z
Name
Configuration
Block
Group
Valency
Core
Valence
3
Li
1 s 2
2 s 1
s
I
1
7.1 Ionic radii in Box  7.2 lead to following radius
ratios:
Si + : 0.26. Al 3+ : 0.36 (tet)/0.46 (oct). Ti 4+ : 0.52. Fe 3+ :
0.55. Fe 2+ : 0.65. Mg 2+ : 0.61. Ca 2+ : 0.91. Na + : 0.94
(8-fold). K + : 1.20.
Co-ordination numbers: 4: Si 4+ , A1 3+ . 6: A1 3+ , Ti 4+ ,
Fe 3+ , Mg 2+ . 8: Ca 2+ , Na + . 12: K + .
7.2 In the higher oxidation state (Fe 3+ , Eu 3+ ), the ion
has fewer valence electrons and there is less mutual
repulsion between them, so ions are smaller than
2+ ions. Ionic potentials: Fe 2+ : 23. Fe 3+ : 41. Eu 2+ : 16.
Eu 3+ : 28. The 3+ ion has a higher polarizing power
than the 2+ ion, and therefore forms a more cova-
lent bond.
7.3 He-He: van der Waals interaction; very weak, so
He is a monatomic gas at room temperature.
Ho-Ho: electronegativity of Ho is between 1.1
and 1.3, therefore metallic bond. Crystalline metal
at room temperature.
Ge-Ge: metallic/covalent bond. Electronegativity
similar to Si in Figure 7.8b. Semiconductor at room
temperature.
5
B
1 s 2
2s 2 2p 1
p
III
3
8
O
1 s 2
2s 2 2p 4
p
VI
−2
9
F
1 s 2
2s 2 2p 5
p
VII
−1
14
Si
1s 2 2s 2 2p 6
3s 2 3p 2
P
IV
4
6.2 Ti [Ar] 4s 2 3d 2 : block d
Ni [Ar] 4s 2 3d 8 : block d
As [Ar] 4s 2 3d 10 4p 3 : block p
U [Rn] 7s 2 6d 1 5f 3 : block f
6.3 Na valency = 1. Oxygen = −2, therefore there are
2 atoms of sodium per atom of oxygen:
Na 2 O
x = 2
y = 1
Similarly
SiO 2
x = 1
y = 2
x = 1 y = 4
MgCl 2 x = 1 y = 2
Valency of scandium is 3, valency of oxygen = −2.
Each Sc combines with 3/2 atoms of oxygen, or 2
Sc atoms combine with 3 oxygen atoms:
SiF 4
Sc 2 O 3
x = 2
y = 3
Similarly
P 2 O 5
x = 2
y = 5
BN
x = 1
y = 1
 
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