Question

Which of the following is the most common solvent used for crystallization?
A. Organic solvent benzene
B. Plain water
C. A salt solution of water
D. Dilute solution of sulphuric acid

Answer 1

The process of arranging the atoms or molecules into a well-defined crystal lattice so that their energetic state could be minimized is referred to as crystallization. In simple words we can define crystallization as the process of converting a chemical from liquid to solid crystals. The process of crystallization takes place in two phases namely; nucleation and crystal growth.

Complete step by step solution
The choice of solvent is the most important decision in the process of crystallization. For the process of crystallization, the ideal solvent is defined as the one which is unreactive, inexpensive, least toxic and has a relatively low boiling point.

Water is known as universal solvent. This is because water is capable of dissolving a wide range of substances which other liquids are not. Also, water has the various characteristics of a good solvent. For example, plain water is completely non-toxic. It has a boiling point of ${\rm{100}}{\;^{\rm{o}}}{\rm{C}}$ which is fairly nice for the process to take place. There are also other solvents which have a very low boiling point. But the fact that makes them not suitable to participate in the process of crystallization is that due to very low boiling point they are highly flammable. Along with all these properties the water has also a unique property of forming hydrogen bonds which leads it to possess similar intermolecular forces as most of the compounds possess.

**Hence, option (B) Plain water, is the correct option.

Note: **
Thus, plain water is the most common solvent used for the process of crystallization. This is because water possesses almost all the characteristics due to which it can be easily added or removed from a system.