The compound which is used as an oxidising agent in many chemical industries is:

$(a)$ State in tabular form the name of the acid and base from which the following salts are formed. Also,mention the nature of the salt,whether it is acidic or basic?
$(i)$ Sodium acetate.
$(ii)$ Ammonium sulphate.

What is meant by "water of crystallisation" in a substance? Explain with an example.

Which of the following salts does not contain water of crystallisation?

How is bleaching powder prepared? Why does bleaching powder $(i)$ not dissolve completely in water?

$(a)$ Write the chemical formula of hydrated copper sulphate and anhydrous copper sulphate. Giving an activity,illustrate how these two are interconvertible.
$(b)$ Write the chemical names and formulae of Plaster of Paris and gypsum.