Question

Which property is mainly used in simple crystallisation to purify a solid?

Options

• Colour of the compound

• Difference in melting points in cold solvent

• Difference in solubility at hot and cold temperatures

• Difference in densities of impurities

Answer 1

Difference in solubility at hot and cold temperatures

Explanation: 

In simple crystallisation, the compound is more soluble in hot solvent and less soluble in cold solvent, so pure crystals separate on cooling.