Question

During an experiment, Neelam and Manish added concentrated sulphuric acid to dry (anhy-
drous) sodium chloride. A gas evolved during the reaction. When Manish placed a dry blue
litmus paper near the mouth of the test tube nothing happened but when he placed a moist
blue litmus paper, it became red. Explain why.

Answer 1

First of all the gas evolved is hydrogen chloride which is an acidic gas. Secondly the litmus on wetting turns red because the water acts as a contact medium for the gas and the litmus paper. Don't get confused it is simple// hope this is helpful

Answer 2

First of all the gas evolved is hydrogen chloride which is an acidic gas. secondly the litmus on wetting turns red because the water acts as a contact medium for the gas and the litmus paper.