(a) What is a universal indicator? For what purpose is it used?
(b) How does a universal indicator work?
(c) Water is a neutral substance. What colour will you get when you add a few drops of universal indicator to test-tube containing water?

(a) Universal indicator is a mixture of different indicators that gives different colours at different pH values. The scale ranges from 0 to 14. It gives an idea of how acidic or basic a substance is.

(b)  Universal indicator is a pH indicator. It shows colour change to identify acid or base. It exhibits several colour changes according to the nature of the solution.

(c)  Water is a neutral substance, pH=7, therefore, it shows a green colour.

 

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Updated on 10-Oct-2022 10:22:36

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