Alcohols post test

Question 1

At room temperature, the first four members of the alcohol homologous series are liquids whereas the first four members of the alkanes are gases

EXPLAIN?

Answer 1

1. Alkanes are non- polar molecules therefore only have induced dipole dipole intermolecular forces.
2. Alcohols have hydrogen bonding between alcohol molecules which are stronger than induced dipole dipole forces, hence they need more energy so there liquids at room temp as there is not enough energy to overcome the hydrogen bonds.

Question 2

Ethane 1,2-diol Is much less volatile than ethanol suggest why?

Answer 2

Ethane 1,2 diol has 2 OH groups ethanol has1 so hydrogen bonds in ethan1,2-diol are stronger / more needs ,ore energy to overcome so less volatile.