Chapter 1. ATOMIC STRUCTURE AND THE PERIODIC TABLE

1
Chapter 5 CHEMICAL BONDS AND MOLECULAR
STRUCTURE
2
(No Transcript)
3
(No Transcript)
4
Electronegativity

• Pauling Scale
• relative attraction of an atom for electrons, its
  own and those of other atoms
• same trends as ionization energy, increases from
  lower left corner to the upper right corner
• fluorine E.N. 4.0

5
Electronegativities of the Elements
6
(No Transcript)
7
Chemical Bond Properties

• Non-polar bonds diff. EN 0
• Polar bonds diff. EN gt 0
• Ionic bonds diff. EN gt 1.5

8
(No Transcript)
9
(No Transcript)
10
(No Transcript)
11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14
(No Transcript)
15
(No Transcript)
16
(No Transcript)
17
Ionic Compounds
18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
(No Transcript)
26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
Covalent Bonding

• Sharing of electrons
• HH
• H-H

30
(No Transcript)
31
Compare O-O and OO. Is OO expected to be
stronger, weaker, or the same strength?
32

• Is OO expected to be
• longer, shorter, or the same length?

33

Shell Model of the Atom

• G.N.Lewis
• 1875-1946
• American Chemist
• Lewis Symbol
• valence shell electrons Group A

34
(No Transcript)
35
Lewis Electron Dot Symbols
36
(No Transcript)
37
(No Transcript)
38
Lewis Structures

• Octet Rule
• In compound formation an atom gains or loses
  electrons, or shares pairs of electrons, until
  its valence shell has eight electrons.

39
(No Transcript)
40
(No Transcript)
41
(No Transcript)
42
(No Transcript)
43
(No Transcript)
44
(No Transcript)
45
(No Transcript)
46
(No Transcript)
47
(No Transcript)
48
(No Transcript)
49
Lewis Structures
CH4 methane
C2H6 ethane
50
Multiple Covalent Bonds

• Double bond 2 pairs shared
• Triple bond 3 pairs shared
• Normally occurs between
• C atoms N atoms O atoms
• a C atom and a N, O or S atom
• a N atom and a O or S atom
• a S atom and an O atom

51
Multiple Covalent Bonds
52
(No Transcript)
53
(No Transcript)
54
(No Transcript)
55
(No Transcript)
56
(No Transcript)
57
(No Transcript)
58
(No Transcript)
59
(No Transcript)
60
(No Transcript)
61
(No Transcript)
62
(No Transcript)
63
(No Transcript)
64
(No Transcript)
65
(No Transcript)
66
(No Transcript)
67
(No Transcript)
68
(No Transcript)
69
(No Transcript)
70
(No Transcript)
71
(No Transcript)
72
(No Transcript)
73
(No Transcript)
74
(No Transcript)
75
(No Transcript)
76
(No Transcript)
77
(No Transcript)
78
Shape PCl3

• Lewis Electron Dot Structure

.. .. .. Cl P Cl .. .. ..
Cl ..
3 bond pairs
1 lone pair gt AB3E
trigonal pyramidal shape
79
Shape IF5

• Lewis Electron Dot Structure
• .. ..
• F F
• .. .. ..
• I F
• ..
• .. ..
• F F
• .. ..

5 bonds pairs
1 lone pair gt AB5E
Square pyramidal shaped
80
Shape IF4-1

• Lewis Electron Dot Structure
• .. .. -1
• F F
• .. .. ..
• I F
• ..
• .. ..
• F
• ..

4 bond pairs 2 lone pairs gt AB4E2 square planar
shape
81
Shape SO3

• Lewis Electron Dot Structure
• ..
• O S O
• .. .. ..
• O
• ..
• 3 bond pairs
• 0 lone pairs gt AB3
• trigonal planar shape

82

• What would be expected to be the shape of
  chloroform, CHCl3?
• see-saw
• square planar
• tetrahedral

83
(No Transcript)
84
(No Transcript)
85
(No Transcript)
86
(No Transcript)
87
(No Transcript)
88
(No Transcript)
89
(No Transcript)
90
(No Transcript)
91
(No Transcript)
92
(No Transcript)
93
(No Transcript)
94
(No Transcript)
95

• Carbon monoxide, CO and carbon dioxide, CO2, are
  linear molecules. Which one is the polar
  molecule
• CO
• CO2

96
(No Transcript)
97
(No Transcript)
98
Potential Energy Curve for H2
99
(No Transcript)
100
(No Transcript)
101
(No Transcript)
102
(No Transcript)
103
(No Transcript)
104
(No Transcript)
105
(No Transcript)
106
(No Transcript)
107
(No Transcript)
108
(No Transcript)
109
(No Transcript)
110
(No Transcript)
111
(No Transcript)
112
(No Transcript)
113
(No Transcript)
114
(No Transcript)
115
(No Transcript)
116

• What would be the name of the hybrid orbitals
  created by joining 1s type, 3 p type and 2 d type
  orbitals?
• spd
• sp3d2
• s3p2d

117
Sigma Bond s

• Bond with the greatest electron density on a
  line connecting the atomic nuclei
• s-s type p-p type s-p type
• s-sp3 type s-sp2 type s-sp type
• p-sp3 type p-sp2 type p-sp type
• sp3 - sp3 type sp2-sp2 type sp - sp type
• etc., including all combinations of s, p, d, and
  hybrid orbitals

118
Pi Bond p

• Bond with the greatest electron density above
  and below a line connecting the atomic nuclei
• p-p type

119
(No Transcript)
120
Bonding in Ethylene
121
Bonding in Acetylene
122
(No Transcript)
123
(No Transcript)
124
(No Transcript)
125
(No Transcript)
126
(No Transcript)
127
Molecular Orbital Diagram
128
(No Transcript)
129
(No Transcript)
130
(No Transcript)
131
(No Transcript)
132
Molecular Orbital Diagram
133
Molecular Orbital Diagram
134
(No Transcript)
135
(No Transcript)
136
(No Transcript)
137
(No Transcript)
138
(No Transcript)
139
(No Transcript)
140
(No Transcript)
141
(No Transcript)
142
(No Transcript)
143
(No Transcript)
144
(No Transcript)
145
(No Transcript)
146
Dipole-Dipole Forces
147
(No Transcript)
148
London (Dispersion) Forces
149
(No Transcript)
150
(No Transcript)
151
Hydrogen Bonds
152
Hydrogen Bonds
153
Bonding in Water
154

• Water, H2O, and methane, CH4, have very similar
  molar masses yet the boiling point for water is
  approximately 200oC higher than that for methane.
  The higher boiling point is due to
• hydrogen bonding in water
• polarity of water molecules
• both of the above
• none of the above

155
Structure of Ice