Question

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

Answer 1

Answer:

dry HCl gas not change the colour of the dry litmus paper,

because in gaseous state dry HCl does not show acidic behaviour although being an acid

or

in other hand in dry form neither the litmus paper is wet nor the HCl is in liquid form.

Answer 2

Answer:

In case of dry HCl gas, there is no presence of water and so, the dye on litmus paper cannot react with the gas. So, any dry gas will not give any change in the colour of litmus paper.