Why does dry HCl gas not change the colour of the dry litmus paper?

Academic Chemistry NCERT Class 10

Dry HCl does not change the colour of dry litmus paper because dry HCl does not undergo dissociation to form ions as there is an absence of an aqueous medium. The colour of the litmus paper changes only when the ions are formed. Hence it does not change the colour of litmus paper.

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Updated on: 14-Mar-2023

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Why does solid baking soda not change the colour of dry litmus paper?
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Would the results of dry baking soda and solution of baking soda on dry litmus paper be same? Why?
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Why does a desert cooler cool better on a hot, dry day?
A student placed a pinch of solid sodium hydrogencarbonate on a strip of red litmus paper. He found that the colour of red litmus paper strip :
Why is solid carbon dioxide called dry ice?

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