Question

Why do esters smell sweet?

Answer 1

The compounds which are volatile have a capability to give the smell. The property of the volatility makes the chemical to smell. Volatile nature to the compound is due to the weak intermolecular forces.

Complete answer:
- In the question it is asked why volatile compounds smell sweet.
- Generally all volatile compounds are sweet in smell.
- Esters are going to be formed by the condensation of carboxylic acid with alcohols.
- The chemical reaction of formation of the esters from the respective acid and alcohol is as follows.
$C{{H}_{3}}COOH+{{C}_{2}}{{H}_{5}}OH\to \underset{Ester}{\mathop{C{{H}_{3}}COO{{C}_{2}}{{H}_{5}}}}\,$
- In the above reaction one mole of acetic acid reacts with one mole of ethanol and forms a compound which is having ester bond in it.
- We have to discuss why esters are sweet in smell.
- All esters are not going to have a smell.
- The ester formed by the acetic acid with ethanol is sweet in smell.
- The intermolecular force of attraction between the esters is weak.
- Due to this less intermolecular force of attraction the ester compounds are volatile in nature.
- There is no existence of the hydrogen bond also in esters.
- This volatile nature of esters makes us smell.

Note:
If the molecules contain RCOOR functional groups in their structures then they are called esters. Mostly esters available in nature in the form of fruits. Fruits contain esters in them. Few types of yeasts also produce esters naturally.