Question

What type of mixture is separated by the technique of crystallisation?
A. Solid – Solid
B. Liquid – Liquid
C. Solid – Liquid
D. Gas – liquid

Answer 1

Hint: Crystallisation is most commonly used as a separation process to separate pure crystals of a product from an impure mixture. Crystallisation is also used to extract pure salt from saltwater, which is an essential use. Crystallisation can also be used to separate impure alum crystals from pure alum crystals.

Complete answer:
A method for separating solids from a liquid solution is crystallisation. Although it is related to precipitation, the precipitation obtained in this process is in the form of a crystal with extraordinarily high purity levels. Impure chemicals can be purified using the crystallisation theory.
The following two types of crystallisation processes can be broadly classified as: Evaporative crystallisation and Cooling crystallisation
The main benefits of crystallisation are:
Through the crystallisation process, a high-purity product can be created in a single step. The crystallised dry items can be packaged and stored immediately. This method uses a small amount of energy and operates at a low temperature.
The following are some common crystallisation examples.
The freezing of water to produce ice cubes and snow.
Gemstone crystals are formed by a process called deposition.
When honey is placed in a jar and exposed to the right circumstances, it crystallises.

Note:
The liquid is above the melting temperature of the solid phase. If in solution, there may be more than one solvent present. Impurities, either dissolved or solid, may be present. Some impurities may have properties that are quite similar to the solute (especially for side-products from organic reactions).