What is an Indicator? Give Examples

An indicator is a substance that changes color when it is added to acidic or basic solutions. It helps to tell whether a solution is an acid or a base.

Here are some common examples of indicators:

• Litmus: Turns red in acids and blue in bases.
• Phenolphthalein: Colorless in acids and pink in bases.
• Methyl orange: Red in acids and yellow in bases.

Indicators are widely used in laboratories and in daily life. For example, litmus paper is used in science experiments to check the acidity or alkalinity of a substance. Indicators can be natural or synthetic. Natural indicators like red cabbage juice and turmeric also show color changes with acids and bases.