Inorganic Chemistry review sheet Exam #1 Ch. 1 General Chemistry

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Inorganic Chemistry review sheet
Exam #1
Ch. 1
General Chemistry review
reaction types: A/B, redox., single displacement, elimination, addition, rearrangement and
solvolysis
types of substances: elements, ionic, molecular
Memorize Periodic Table
Periodic Table: metal/metalloid/non-metal
Groups (vertical)
alkali metals, alkaline earth metals, transition metals.,
pnictogens, chalcogens, halogens, noble gas
Periods (horizontal)
Thermodynamics
1st Law: E = q + w
Gibbs Free Energy, ΔG = ΔH – TΔS
Enthalpy, ΔH = qp
Entropy, ΔS disorder, S = k lnW
Stable (ΔG = +) vs. unstable (ΔG = –)
Kinetics
Inert (slow) vs. Labile (fast)
reaction profile: E vs. reaction progress
Ch. 2
The atom
Quantum Theory: Plank and Einstein. E is quantized
Rutherford’s Au foil experiment: atomic model
Bohr model of the atom: E given to the atom puts the e– in an excited state, drops back down to the
ground state (a specific orbit; a specific E drop, a specific color).
Visible line spectrum of H2:
E is artificially quantized via the orbits from the Bohr model
deBroglie: e– has particle-like and wave-like characteristics. Standing waves are quantized;
quantization a natural result of the model.  = h / mv
e–: Particle-like nature: Einstein (photoelectric effect)
Wave-like nature: Davisson –Germer
Schrödinger wave equation uses both properties of e–
or simply, H = E
where H is the Hamiltonian operator ∂2Y/∂ wrt: x, y, z
Ψ ‘is’ the e–. The Ψ describes the e– in terms of location and E.
Goal: Describe an e– in an atom via the wavefunction: 
 has no physical meaning, so Born interpretation (Ψ2 = probability of finding the e–)
Acceptable s mathematically must be: 1. Normalized 2. Single valued at x,y,z 3. Continuous 4. Finite
 is quantized with only certain values (quantum numbers: n, ℓ, mℓ)
Can more easily separate out angle () and distance data (r) if spherical polar coordinates are used
instead of Cartesian coordinates.
E exactly solvable for H and 1e– species:
per atom
Ψ consists of R(r) (radial function) (R(r)2 = probability as a function of distance) and Y (angular
function; spherical harmonic) (Y2 = probability as a function of angle).
4 Quantum #s:
n: Principle QN; E and size. Any whole # integer from 1 to ∞ (∞ means e– is completely removed
from atom)
ℓ: Orbital angular momentum (azmithul QN); shape from e– movement. Any whole # value up to n–1
mℓ : Magnetic QN; orientation, moving e– generates a magnetic field. Values from –ℓ up to +ℓ
ms : e– can be spin up (+1/2) or down (–1/2)
Wavefunction Equations and Orbital plots
Radial - R
Radial Density – R2
Radial Probability – “onion shell” 4πr2R2
s, p, d (know shape, name, label axes), f orbitals
gerade vs. ungerade (i)
What is the interpretation of the drawing? Wavefunction itself (no physical meaning), angular part of
wavefunction squared – probability at angles (out to infinity), or contour plot – 90% probability
(includes R2 and, hence, n).
Looking at a one e– atom: all orbitals with the same n are degenerate because the one e– isn’t being
shielded by any other e–s. Atoms with more than one e– show differences in E between orbitals with
the same n because of shielding. (s orbitals shield (see below) best, and thus are lowest in E).
Can model with Self Consistent Field (SCF) model.
E for more than 1e– species:
Z*
s, p:
d, f:
Effective nuclear charge
per atom
Z* = Z – S
Z; atomic number (# of p+)
S; Shielding (screening) constant
close to nucleus: screened less by inner e–. More effective at screening outer e–.
screened more by inner e– & poor at screening.
Ground state e– configuration from Periodic Table (Pauli Exclusion Principle, Aufbau and Hund’s
Rule;
, where N, # of e– with parallel spin.  over all orbitals.
K, exchange integral (1(1)2(2) with 1(2)2(1)) ). Valence e–s
Exchange Energy – maximized with number of parallel spins
Ground state e– configuration anomalies (know: Cr (exchange energy) and Cu)
TM Anomalous e– Configurations
Periodic Table should be based on atomic numbers (Z) NOT e– filling anomalies!
Orbital filling: Paramagnetic, contains unpaired e–s, attracted to a magnetic field.
Diamagnetic, contains paired e–s, repelled by a magnetic field.
Slater’s Rules (Shielding):
Screening constant estimated from Slater's Rules:
Divide orbitals in groups of n & s,p or d or f:
1s
2s,2p 3s,3p 3d
1.
e– of interest s or p:
each contribute 0.35 (35%)
a.
e–’s in same group
b.
n–1
each contribute 0.85 (85%)
c.
n – 2 & below
each contribute 1.00 (100%)
2.
e– of interest d or f:
a.
e–’s in same group
b.
n – 1 & below
4s,4p 4d
4f
each contribute 0.35
each contribute 1.00
Periodic Trends: Size, IE, EA, e– configurations of ions (and reasoning behind all)
Size: Lanthanide contraction makes 3rd to 4th row of transition metals smaller than
expected
IE1 (1st ionization energy; one e– removed), IE2 (2nd ionization energy; 2nd e– removed)…
EA1 (1st e– affinity; 1st e– added), EA2 (2nd e– affinity; 2nd e– added)… (if adding e– is favorable,
the EA value will be negative).
Ch. 3
Symmetry operation
Symmetry elements (point symmetry):
1. Center of symmetry (or inversion) i, point
2. Rotation (or proper) axis Cn, line
3. Mirror , plane
Types: h  ┴ to the principle axis, Cn
v  containing the principle axis, Cn
d s bisecting 2 C2’s
4. Rotation–reflection (or improper) axis Sn, line
5. Identity E, no element
Group Theory
When all the symmetry elements in a molecule are collected, it is found that they have the properties
of a mathematical group.
1.
Product of 2 elements of a group the same as another element of the group. AB = C
2.
There is the identity operator, E. EA = A
3.
Every element has an inverse which is an element of the group. A–1A = E
4.
Associative law holds: A(BC) = (AB)C
Point Group: All the mathematical operations (symmetry elements) constitute a group; the
symmetry elements intersect in at least one point. (If all of the symmetry operations
were performed, at least one point remains unchanged).
Point groups represented by Schoenflies symbol. Shorthand for all the symmetry of an object
(molecule).
Some ex.s of point groups:
C1
E
Ci
E, i
Cs
E, s
E, C2
C2
D3
E, 2 C3, 3 C2
C2v
E, C2, v(xy), v(yz)
C2h
E, i, C2, h
D2d
E, 2 S4, C2, 2 C2′, 2 d
D4h
E, 2 C4, C2, 2 C2′, 2 C2′′, i, 2 S4, h, 2 v, 2 d
E, 8 C3, 3 C2, 6 S4, 6 d
Td
Oh
E, 8 C3, 6 C2, 6 C4, 3 C2, i, 6 S4, 8 S6, 3 h, 6 d
Cv
E, 2 C,  v
Dh E, 2 C,  v, i, 2 S ,  C2
E, 12 C5, 20 C3, 15 C2, i, 12 S10, 20 S6, 15 
Ih

Note: There is no Dnv, Ov or Tv
Do not have to find all the symmetry to assign point group:
1.
Linear? Cv or Dh
2.
High symmetry? Multiple Cn , n > 2 Ix, or Ox
3.
Highest Cn Tx, Cnx or Dnx
4.
┴ C2’s? Dnx
5.
Mirrors? h: Cnh or Dnh ; just v(d): Cnv or Dnd
Assigning Point Groups (know how to draw in necessary symmetry elements to validate the Point
Group chosen):
Character Tables (see Character Tables): Point Group symbol, Mulliken symbol, Symmetry
Elements, Irreducible Representations, Characters, orbitals, rotation axes…
Applications of Symmetry & Group Theory
Optical Activity, dipole moments, IR (and Raman) Spectroscopy, NMR, Bonding and Orbitals,
Crystallography
Can apply the symmetry elements contained in the Group to see what happens to the molecule (orbitals
in the molecule): Symmetry operations can leave a vector: unchanged, 1; inverted, –1;
or translated, 0
The mathematical result can be used to see if a stretch of a bond will be seen in the IR spectrum, can
use results to make MO diagrams, etc… Simpler approaches are knowing the point group of a
molecule allows the prediction of the number of peaks in an NMR spectrum.
IA
VIIIA
1
2
H
1.008
IIA
IIIA
IVA
VA
VIA
VIIA
3
4
5
6
7
8
9
Li Be
6.941
9.012
11
12
Na Mg
Periodic Table of the Elements
22.990
24.305
IIIB
IVB
VB
VIB
19
20
21
22
23
24
K Ca Sc
VIIB
25
VIII
26
27
28
He
4.003
10
B
C
N
O
F
Ne
10.811
12.011
14.007
15.999
18.998
20.180
13
14
15
16
17
18
IB
IIB
Al
Si
P
S
26.982
28.086
30.974
32.065
35.453
Cl Ar
39.948
29
30
31
32
33
34
35
36
Ti
V
39.098
40.078
44.956
47.867
50.942
51.996
54.938
55.845
58.933
58.693
63.546
65.409
69.723
72.64
74.921
78.96
79.904
83.798
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
I
Xe
Rb Sr
Y
Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te
85.468
87.62
88.906
91.224
92.906
95.94
(98)
55
56
71
72
73
74
75
101.07 102.906 106.42 107.868 112.411 114.818 118.710 121.760 127.60 126.904 131.293
76
77
Cs Ba Lu Hf Ta W Re Os Ir
78
79
80
81
132.905 137.327 174.967 178.49 180.948 183.84 186.207 190.23 192.217 195.078 196.967 200.59 204.383
87
88
103
104
105
106
107
108
109
110
111
112
113
Fr Ra Lr Rf Db Sg Bh Hs Mt Ds Rg Cn C
(223)
226.025
82
83
84
85
207.2
208.980
(209)
(210)
(222)
114
115
116
117
118
C
(267)
(270)
(271)
(270)
(277)
(278)
(281)
(281)
(285)
((284)
(289)
)
(289)
C
(262)
(291)
(294)
57
58
59
60
61
62
63
64
65
66
67
68
69
70
C
C
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
138.906 140.116 140.908 144.24
89
90
91
Ac Th Pa
92
(145)
93
150.36 151.964 157.25 158.925 162.500 164.930 167.259 168.934 173.04
94
95
96
97
98
99
100
101
102
U Np Pu Am Cm Bk Cf Es Fm Md No
227.028 232.038 231.036 238.029 237.048
(244)
(243)
86
Pt Au Hg Tl Pb Bi Po At Rn
(247)
(247)
(251)
(252)
(257)
(258)
(259)
(294)
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