Question

Explain diffusion of copper sulphate into water .

Answer 1

Pure Copper Sulphate ( ${CuSO}_4$ ) is usually available in the form of blue-coloured ionic crystals. When the crystals of pure ${CuSO}_4$ are added in $H_{2}O$ then the solvation enthalpy of $H_{2}O$ -molecules becomes greater than the lattice enthalpy of ${CuSO}_4$ ionic solid. As a result, water molecules begin to come between the ${Cu}^{2+}and{SO}_4^{2-}$ ions and this process is commonly called Diffusion in the macroscopic terms. Thus, the ionic force of attraction between the cation (${Cu}^{2+}$ ) and anion (${SO}_4^{2-}$ ) gets eventually weaker with time and the two ions get separated.

After some time of keeping the solution undisturbed, the strong electrolyte of copper sulphate gets prepared, known as the Blue Vitrol.