Answer the following questions related to salts and their preparations:

(a) What is a 'salt' ?

(b) What kind of salt is prepared by precipitation?

(c) Name a salt prepared by direct combination. Write an equation for the reaction that takes place in preparing the salt you have named.

(d) Name the procedure used to prepare a sodium salt such as sodium sulphate.

(a) Salt is a compound formed by the partial or total replacement of the ionisable hydrogen atoms of an acid by a metallic ion or an ammonium ion.

(b) An insoluble salt can be prepared by precipitation.

(c) A salt prepared by direct combination is Lead(II) Sulphide.
Pb + S $\xrightarrow{\space\Delta\space}$ PbS

(d) By neutralisation of alkali (caustic soda) with acid (dilute sulphuric acid):
2NaOH + H₂SO₄ ⟶ Na₂SO₄ + 2H₂O