Question

What is meant by crystallization? How is copper sulfate purified from its impure sample by this method? Explain the procedure.

Answer 1

Crystallization:

1. The process of separating a pure solid in the form of crystals from a solution containing impurities is known as crystallization.
2. It is a process through which the atoms of a substance arrange themselves in a well-defined three-dimensional lattice and consequently, minimize the overall energy of the system.
3. The process of crystallization offers a wide range of applications in the field of the pharmaceutical industry in the synthesis and isolation of active pharmaceutical ingredients (APIs).

The copper sulfate is purified from its impure sample using the technique of crystallization. The steps involved in this method are:

1. Take the impure sample of copper sulfate in a beaker.
2. Dissolve the sample in the minimum amount of water.
3. Filter the impurities if any and collect the solution in a china dish.
4. Evaporate the excess water to make a saturated solution of copper sulfate.
5. Cover the china dish with a filter paper and allow it to cool slowly to room temperature.
6. Crystals of pure copper sulfate are formed.

Therefore, crystallization can be used to purify copper sulfate from its impure sample.