Indicators

Action on indicators

An indicator is a substance that changes color when it comes in contact with an acid or a base. Different indicators change color at different pH levels, and they help in identifying whether a solution is acidic, neutral, or basic.

Examples of indicators include:

1. Litmus: Turns red in acidic solutions and blue in basic solutions.
2. Methyl Orange: Turns red in acidic solutions and yellow in basic solutions.
3. Phenolphthalein: Remains colorless in acidic solutions and turns pink in basic solutions.

Table of indicators

Below is a table showing the color change of various indicators in acidic and basic solutions:

Indicator	Acidic Solution	Basic Solution
Litmus	Red	Blue
Methyl Orange (MO)	Red	Yellow
Phenolphthalein (POP)	Colorless	Pink
Bromide Blue	Yellow	Blue