Question

1) Rank the following molecules in order of increasing boiling point: methoxymethane, propane, ethanoic acid, ethanol.

Please show step by step how to solve this

Answer 1

The order of boiling point is as follows

propane< methoxymethane < ethanol < ethanoic acid

This order is followed mainly due to the polar and a-polar nature of compounds

Propane is a hydrocarbon has no interaction between neighbouring molecules other than wanderwaals forces hence it can be easily evapourated simillarly methoxy methane is an ether and can be easily evapourated

where in ethanol has a polar OH group which forms hydrogen bonds with the neighbouring molecules hecne needs more energy to break these bonds and hence the boiling point increases.

In ethanoic acid due to the presence of carboxyl group the hydrogen bonding is much stronger and hence boiling point increases further.