Unit 2 - Nature's Chemistry (Alcohols)

Question 1

What is a primary alcohol?

Answer 1

An alcohol in which the hydroxyl group (–OH) is attached to a carbon atom with at least two hydrogen atoms. This will only occur when the hydroxyl group is at the end of the molecule chain.

Question 2

What is a secondary alcohol?

Answer 2

An alcohol in which the hydroxyl group (-OH) is attached to a carbon with only one hydrogen atom attached. This can happen somewhere in the middle of a carbon chain.

Question 3

What is a tertiary alcohol?

Answer 3

An alcohol in which the hydroxyl group is attached to a carbon with no hydrogen atoms attached. This will normally mean that the hydroxyl group is joined to the same carbon atom as a branch.

Question 4

What are alcohols with two -OH groups called?

Answer 4

Diols

Question 5

What are alcohols with three
-OH groups called?

Answer 5

Triols

Question 6

Why do alcohols have higher boiling points than alkanes?

Answer 6

The hydroxyl groups in alcohol molecules are responsible for hydrogen bonding between the alcohol molecules. As greater energy is required to overcome these strong intermolecular forces, the melting points and boiling points of alcohols are higher than those of alkanes with a corresponding chain length. Alcohols with a greater number of hydroxyl groups will have even higher boiling points.