Choosing the substances from the list given : dil. sulphuric acid, copper, iron, sodium copper (II) carbonate, sodium carbonate, sodium chloride, zinc nitrate. Write balanced equation for the reaction which would be used in the laboratory to obtain copper (II) sulphate.

State the inference drawn from the observation:

Salt $\mathrm{S}$ is prepared by reacting dilute sulphuric acid with copper oxide. Identify $\mathrm{S}$.

From the list of salts — $\mathrm{AgCl}, {\mathrm{MgCl}}_2, {\mathrm{NaHSO}}_4, {\mathrm{PbCO}}_3, {\mathrm{ZnCO}}_3, {\mathrm{KNO}}_3, \mathrm{Ca}{\left({\mathrm{NO}}_3\right)}_2$, choose the salt that most appropriately fits the description given below:

a deliquescent salt