Question

Identify the olfactory element in the following: vanilla onion and clove, Justify your answer.

Answer 1

Hint :Sometimes some substances can be distinguished between acid and base just by dissolving substances that are named as olfactory indicators. These indicators change their smell according to if they are acid or base.

Complete Step By Step Answer:
An olfactory indicator is a substance which changes smell according to in which it is dissolved that is acid or base. These are used in olfactory titration in the laboratories for detecting acid and base.
Any substance which can change its smell in acid and in base can be considered as an olfactory substance.
Vanila – Vanila is an olfactory indicator as it has two different smells in the presence of acid and base. Vanilla in the presence of acid retains its smell. Vanilla loses its complete smell in the basic solution.
Onion- Onion is an olfactory indicator where it has two and distinct smells in presence of acid and base. Onion in acid retains its normal. Onion in the presence of a basic solution, loses its smell very ghastly, completely odourless.
Clove- Clove is an olfactory indicator as it has two distinct smells in presence of acid and base respectively. Clove in the presence like vanilla and onion retains its smell while in the presence of basic solution it loses its smell like vanilla and onion only.
Vanilla, onion and clove all are olfactory indicators, they in the presence of acidic solution retain their smell while in the presence of basic solution lose their distinct smell.

Note :
Turmeric changes its colours in acidic solution and basic solution, it is an indicator but an olfactory indicator. It has yellow colour in acidic solution and blue in bases.