why does litmus paper turn its colour into red when it is dropped in acid and blue when it is dropped in bases

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Solution

Red litmus contains a weak diprotic acid. When it is exposed to a basic compound, the hydrogen ions react with the added base. The conjugate base, formed from the litmus acid, has a blue color, so the wet red litmus paper turns blue in alkaline solution.
you dont have to study the mechanism of this.

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Similar questions

What does exactally happen with litmus paper when it is being dropped in either base or acid to change its colour

Q. Can we use the same blue litmus paper that turned into red when poured a drop of acid, again to obtain blue litmus paper again.

Q. Read the following statements:
I. When a red litmus paper is dipped into reaction mixture of a saponification reaction, it turns blue and the reaction is exothermic.
II. When a blue litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is exothermic.
III. When a red litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is endothermic.
IV. When a blue litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is endothermic.
Which of the above statements are correct?

Read the following statements

(i) When a red litmus paper is dipped into reaction mixture of a saponification reaction, it turns blue and the reaction is exothermic.

(ii) When a blue litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is exothermic

(iii) When a red litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is endothermic.

(iv) When a blue litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is endothermic.

Which of the above statements are correct

When a blue litmus paper is put in an acidic Solution, it turns red. Can the red litmus which has been formed used to indicate basicity?

In other words, can litmus paper which has changed its colour once be reused?

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