Question

from which substance natural indicator are prepared? explain any one in detail with procedure. ​

Answer 1

Natural indicators are prepared by many natural substances like turmeric, litmus, and chinarose flower.

Let me explain litmus indicator.

It is prepared from lichens. It's natural colour is purple, but it is eventually turned to blue and red litmus. It can be used as a litmus solution or litmus paper. The litmus paper is a very common indicator to test acids and bases. The test is called the litmus test.

For testing acids:

1) Dilute some lemon juice with water, in a test tube.

2) Take a strip of blue litmus paper.

3) Take the lemon juice in a dropper and pour it on the litmus paper.

4) It will gradually turn to red.

So, acids turn blue litmus to red.

For testing bases:

1) Make a baking soda solution in a test tube.

2) Take a strip of red litmus paper.

3) Take the baking soda solution in a dropper and pour it into the litmus paper.

4) It will gradually turn to blue.

So, bases turn red litmus to blue.

Please note, that the colour of red litmus paper will remain unchanged in the addition of an acid, and the colour of the blue litmus paper will remain unchanged on addition of a base.