why blue litmus paper turns red when dipped in base

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Solution

It is red litmus paper turns blue when dipped in base.

Litmus paper is used as a pH indicator to determine whether the solution is acidic or basic. Substances with a pH level of 7 are neutral. Ones with a pH level below 7 are acidic. Ones with a pH above 7 are basic.

Litmus paper will work on pH principle. Litmus paper will have a colour coding so if we want to dip into some solution, it would change the colour depending on the pH.

Acids turn blue litmus paper red, while bases turn red litmus blue. Neutral solutions (neither base nor acid) do not change its colour.

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Similar questions

Q. In which condition red litmus paper turns blue?

When a red litmus paper is dipped in the aqueous solution of $X$ there is no change in colour.
When a blue litmus paper is dipped in the same solution it turns red.
Which among the following options can be the chemical $X$ ?

What happens when [5 MARKS]

a) A red litmus paper is dipped in a solution of calcium hydroxide.

b) A red litmus paper is dipped in a solution of sodium chloride.

c) A blue litmus paper is dipped in lemon juice.

d) A red litmus paper is dipped in distilled water.

e) A solution of sodium hydroxide is added to turmeric.

Q. What do we observe on pouring acetic acid on red blue litmus papers ?
(a) Red litmus remains red and blue litmus turns red.
(b) Red litmus turns blue and blue litmus remains blue.
(c) Red litmus turns blue and blue litmus turns red.
(d) Red litmus becomes colourless and blue litmus remains blue.

Q. Dry ammonia has no action on litmus paper, but a solution of ammonia in water turns red litmus paper blue. Why?

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