The Process of Dissolving Copper Sulphate in Water

Adding a few crystals of copper sulphate to water will result in a color change over time, as the crystals dissolve and the solution turns blue. This process can be explained in detail as follows:

Dissolving of Copper Sulphate
When the few crystals of copper sulphate are added to water, they begin to dissociate into their constituent ions. Copper sulphate is an ionic compound composed of copper ions (Cu2+) and sulphate ions (SO4 2-). In its solid form, the copper sulphate crystals contain a lattice of these ions held together by electrostatic forces.

Ionization of Copper Sulphate
As the crystals come in contact with water, the water molecules surround and interact with the copper sulphate ions. The positively charged hydrogen atoms in water molecules are attracted to the negatively charged sulphate ions, while the negatively charged oxygen atoms in water molecules are attracted to the positively charged copper ions. This attraction weakens the electrostatic forces holding the lattice together, causing the copper sulphate crystals to ionize.

Hydration of Copper Sulphate Ions
Once the copper sulphate crystals have dissociated, the individual copper ions and sulphate ions become surrounded by water molecules. This process is called hydration. The water molecules form a shell around each ion, solvating them and preventing them from recombining. During this hydration process, the blue color of the copper ions becomes more apparent as they interact with the surrounding water molecules.

Formation of Copper Sulphate Solution
As more and more copper sulphate crystals dissolve, the concentration of copper ions in the solution increases. This leads to the formation of a copper sulphate solution. The solution appears blue due to the absorption and scattering of light by the copper ions. The blue color is a characteristic property of copper ions in an aqueous solution.

Conclusion
In conclusion, when a few crystals of copper sulphate are added to water, they dissolve and form a copper sulphate solution. The process involves the ionization of the copper sulphate crystals, followed by the hydration of the individual copper and sulphate ions. As the concentration of copper ions increases, the solution turns blue due to the absorption and scattering of light.

it's due to diffusion