Acids, Bases & Salts (C10)

1 g of solid sodium chloride is taken in a clean and dry test tube and 2 mL of conc. sulphuric acid is added to it. If the gas evolved is tested first with dry and then with wet blue litmus paper, in which case will the litmus paper change colour? Give reason for your answer. What inference can be drawn about the nature of the evolved gas ? Support your answer with chemical equation for the reaction.

Answer

Wet blue litmus paper

Reason: Hydrogen ions are produced by HCl in the presence of water.

It has acidic nature.

HCl + H2O → H3O+ + Cl-