Question

why does dry HCL gas not change the colour of dry Litmus Paper​

Answer 1

Answer:

we know that the colur of litmus paper is changed by H+ ions bcz of acid.Dry HCL does not dissociate to give H+ ions.Acid dissociate to give ions only in aq solution. In this , HCL is not in aq form nor litmus ppr is wet, so the colour of litmis ppr does not change

Answer 2

$\bf\huge\underline\orange{Question}$

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

$\bf\huge\underline\purple{Answer}$

Dry HCL gas cannot ionise. For any reason to take place the dry HCL gas has to first form ions. HCL ionises in aqueous medium to form H+ ions. Hence, it does not change the colour of dry litmus paper. To show its acidic behaviour it needs wet litmus paper.