1. Chapter 10 Worked Example 1
Explain the trend in the boiling points of the hydrogen halides:
HCl, -85 oC; HBr, -67 oC; HI, -35 oC.
- Electronegativity differences: HCl > HBr > HI
- Number of electrons and London forces: HCl < HBr < HI
→ not by dipole-dipole forces, but by London forces

2. Chapter 10 Worked Example 2

3. Chapter 10 Worked Example 3

4. Chapter 10 Worked Example 4
Identify the kinds of intermolecular forces that might arise between
molecules of each of the following substances:
(a) NH2OH; (b) CBr4; (c) H2SeO4; (d) SO2
Solution
London forces, dipole-dipole forces, hydrogen bonding
London forces
London forces, dipole-dipole forces

5. Chapter 10 Worked Example 5
Suggest, giving reasons, which substance in each of the following
pairs is likely to have the higher normal melting point (Lewis
structures may help your arguments):
HCl or NaCl; (b) C2H5OC2H5 (diethyl ether) or C4H9OH (butanol);
(c) CHI3 or CHF3; (d) C2H4 or CH3OH.
Solution

6. Chapter 10 Worked Example 6

7. Chapter 10 Worked Example 7
Predict how each of the following properties of a liquid varies as
the strength of intermolecular forces increases and explain your
reasoning: (a) boiling point; (b) viscosity; (c) surface tension.
Solution