1. Chapters 5/6
Chemical Bonding

2. 2 Types of bonds
A + B
A:B
Shared Pair
Covalent
A+ :B-
Ionic . .

3. Bonding Types Ionic 3.3 2.1 0.5 0.0 Polar Covalent 100% 50% 5% 0%
Percent Ionic
100%
50% 5% 0%
Difference in Electronegativity
3.3
2.1
0.5
0.0
Ionic
Nonpolar
Covalent
Polar Covalent

4. Types of Bonds Cs - F 4.0 – 0.7 = 3.3 Ionic Bond 3.0 – 2.1 = 0.9
H - Cl
Polar Covalent
H - H
2.1 – 2.1 = 0.0
Nonpolar Covalent

5. Polar Covalent d+ d- Polar Covalent – unequal sharing
Shared electron cloud Cl H d+ d-
(Slightly positive)
(Slightly negative)
Polar Covalent – unequal sharing

6. Nonpolar Covalent H H
Nonpolar Covalent – equal sharing

7. Properties of ionic compounds
Composed of positive and negative ions
Ionic compounds form crystals

8. Ionic vs. Covalent compounds
Harder
Higher melting point
Higher boiling point
Form crystals
Form electrolytes
Salt
Lower melting point
Lower boiling point
Doesn’t form electrolytes
Sugar

9. Metallic bonds
Sheet of positive ions surrounded by mobile electrons

10. Metallic bonding Electrons are randomly spaced Properties of metals
Free to move around
Good conductors of heat and electricity
Called “electron sea”
Properties of metals
Malleable – able to be bent or shaped
Ductile – able to be drawn into a wire

11. VSEPR Valence shell electron pair repulsion theory Linear – AB2
Electrons want to be as far apart as possible
“molecular geometry”
Linear – AB2
Bent – AB2e2
Triangular Planar – AB3
Tetrahedral – AB4