Question

Dry hcl cannot change the colour of dry litmus paper give reason

Answer 1

Dry HCl dies not produce any ions (H+) for only they convert the color of the paper.

Only aqueous or molten condition produces ions.

Answer 2

HCl produces H+ ions only when dissolved in water. Since the HCl taken is dry , it does not produces any ions. Only if ions are produced, there may be a chance for having a color change in litmus paper. So Dry HCl does not make any color change on the dry litmus paper.

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