Solutions of sodium carbonate, potassium chloride and ammonium sulphate are taken in separate beakers.

Dip litmus paper (red, blue) in each beaker
i. Observe the colour change of litmus paper and tabulate.

ii. Name the acids and alkalies that react with each other to form each of the salts given above?
iii. Can you explain the colour change of the litmus paper on the basis of the nature of the acid and alkali that react with each other to form the salt?
(Hint: potassium chloride is a salt formed by the reaction between strong acid and strong alkali)