Question

1) Fruity group

a) Do all esters smell fruity? If not, which ones do not?

b) Does length of a straight chain affect the type of smell?

Answer 1

a) No, all esters do not smell fruity.

Examples: The esters having low molar mass, i.e. those esters having short chain structure.

Ethyl acetate (CH₃C(=O)OCH₃) is an ester but doesn't smell fruity. It smells like paint.

b) Yes, the length of a straight chain affects the type of smell.

Effect: As the molar mass of an ester increases, i.e.as the chain length of an ester molecule increases, there will be an increase in weak van der Waal's intermolecular forces, which allow the ester molecules enter into the gas phase and reach our nose, as a result, more fruity smell will be observed.