Question

How is a universal indicator obtained? How is the wide range of pH of solution tested by it?

Answer 1

1. A universal indicator is obtained by mixing several indicators (like methyl orange, phenolphthalein, etc.) so that it shows different colours at different pH values.
2. It is used to test the pH by adding it to a solution and comparing the resulting colour with a pH colour chart, which indicates the pH value over a wide range (1-14).