Answer: sodium chloride
and sulphuric acid
are reactants .
sodium sulphate
and hydrochloric acid
are products.
Step-by-step explanation:
Reactants of a chemical reaction is defined as the substances which take part in a chemical reaction and undergoes a chemical change. Reactants are written on left side of the arrow.
Products are defined as the substance which are formed at the end of the chemical reaction.Products are written on the right side of the arrow.
Double displacement reaction is one in which exchange of ions take place.

Thus sodium chloride
and sulphuric acid
are reactants and sodium sulphate
and hydrochloric acid
are products and all are present in aqueous (aq) state.