Question

What are indicators? What are they used for? Give some examples of naturally occurring indicators.

Answer 1

Substances that exhibit a change of colour or odour when added to acidic, basic and neutral solutions are called indicators.

Visual indicators show different colours in presence of an acidic and a basic solution. Similarly, olfactory indicators exhibit different odour when added to acids or bases. Thus, they help us in deciding whether a given solution is acidic or basic in nature.

Some of the naturally occurring indicators are china rose petals, litmus, turmeric, etc.