Question

Give one test to distinguish between zinc sulphate and zinc chloride solution.

Answer 1

• Zinc sulphate and zinc chloride solutions are distinguished by adding barium chloride solution to both.
• Zinc sulphate on reaction with barium chloride, forms a white precipitate of barium sulphate, which is insoluble in mineral acids.

$$\begin{gathered} {\mathrm{ZnSO}}_4\left(\mathrm{s}\right)+{\mathrm{BaCl}}_2\left(\mathrm{aq}\right)\to {\mathrm{BaSO}}_4\left(\mathrm{s}\right)+{\mathrm{ZnCl}}_2\left(\mathrm{aq}\right) \\ \mathrm{Zinc}\mathrm{sulphate}\mathrm{Barium}\mathrm{chloride}\mathrm{Barium}\mathrm{sulphate}\mathrm{Zinc}\mathrm{chloride} \end{gathered}$$

• Zinc chloride solution does not react with barium chloride solution.