A student placed a few drops of a liquid over a portion of the red litmus paper as shown here. He observed that the red litmus paper turned blue. The liquid could be :
(1) dilute hydrochloric acid (2) dilute sodium hydroxide
(3)water (4)dilute acetic acid
"

Correct answer: (2) dilute sodium hydroxide

Explanation: Litmus is an acid-base indicator. Acids turn blue litmus to red and bases turn red litmus to blue. As sodium hydroxide is a base, it will turn red litmus paper to blue.

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Updated on: 10-Oct-2022

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(1) dilute hydrochloric acid	(2) dilute sodium hydroxide
(3)water	(4)dilute acetic acid

(1) dilute hydrochloric acid	(2) dilute sodium hydroxide
(3)water	(4)dilute acetic acid

A student placed a few drops of a liquid over a portion of the red litmus paper as shown here. He observed that the red litmus paper turned blue. The liquid could be :(1) dilute hydrochloric acid (2) dilute sodium hydroxide(3)water(4)dilute acetic acid"

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A student placed a few drops of a liquid over a portion of the red litmus paper as shown here. He observed that the red litmus paper turned blue. The liquid could be :
(1) dilute hydrochloric acid (2) dilute sodium hydroxide
(3)water (4)dilute acetic acid
"