2. Molecular Representations

List each set of compounds in order of increasing boiling point.

a. hexane, octane, and decane

Rank the following compounds from highest boiling to lowest boiling:

Explain the following:

a. 1-Hexanol has a higher boiling point than 3-hexanol.

Explain why

c. H₂O (100 °C) has a higher boiling point than HF 120 °C2.

d. HF 120 °C2 has a higher boiling point than NH₃ (-33 °C).

Which of the following compounds forms hydrogen bonds between its molecules?

1. CH₃CH₂OCH₂CH₂OH

2. CH₃CH₂N(CH₃)₂

3. CH₃CH₂CH₂CH₂Br

In each pair of compounds, which compound has the higher boiling point? Explain your reasoning.

c. 2,2,5-trimethylhexane or nonane

In each pair of compounds, which compound has the higher boiling point? Explain your reasoning.

b. nonane or 2-methylheptane

In each pair of compounds, which compound has the higher boiling point? Explain your reasoning.

a. octane or 2,2,3-trimethylpentane

List each set of compounds in order of increasing boiling point.

b. Octane, (CH₃)₃C—C(CH₃)₃ and CH₃CH₂C(CH₃)₂CH₂CH₂CH₃

Choose the molecule in each pair you'd expect to have the higher boiling point. Explain your reasoning.

(b)

Ionic compounds like sodium acetate have a high melting point. Despite this, they are highly soluble in water. Why?

Despite methylcyclohexane (98.2 amu) having a higher molecular weight than toluene (92.1 amu), toluene melts at a higher temperature. Why? [Think about how the molecules can interact with each other based on their shape.]

Choose the molecule in each pair you'd expect to have the higher boiling point. Explain your reasoning.

(a) eicosane ( C₂₀H₄₂) vs pentadecane

Draw a picture of the hydrogen bonding in methanol.

Which has

g. the higher boiling point: 1-bromopentane or 1-chloropentane?