Why crystallization technique is preferred over evaporation?

Pure crystals of the substance of interest are recovered using crystalization

It can be used to obtain substances that decompose on heating.

Explanation:

Crystalization is the process of converting a liquid solution to a crystalline solid. It is a common method of extracting the solid product of a reaction from solution. It can also be a separation method especially for obtaining pure crystals from a solution.

Crystalization does not require heating. Common methods of inducing crystalization include; addition of crystals of the same substance as seeds or scratching the vessel containing the solution.

The advantage of crystalization over evaporation is that it can be used to recover substance that decompose on heating. Also crystalization yields pure crystals of the substance of interest compared to evaporation in which soluble impurities may not be completely removed.

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