(a) What happens when an aqueous solution of sodium sulphate reacts with an aqueous solution of barium chloride ?
(b) Write the balanced chemical equation for the reaction which takes place.
(c ) State the physical conditions of reactants in which the reaction will not take place.
(d) Name the type of chemical reaction which occurs.
(e) Give one example of another reaction which of the same type as the above reaction.

Explanation

A white precipitate of barium sulphate is immediately formed when the two aqueous solutions are mixed in a test tube. No reaction will be possible if the two reactants are in the solid state. The balanced chemical equation for the double displacement reaction is :
`BaCl_(2)(aq) + Na_(2)SO_(4)(aq) to underset("(White ppt.)")(BaSO_(4)(s)) + 2NaCl(aq)`