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

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Chapter 2 NCERT Class 10 Science SOLUTIONS

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

Question:

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

Answer:

Dry hydrochloric gas does not contain free hydrogen ions. Hence it does not show acidic character. Due to this it does not change the colour of litmus paper.

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