A student purchases common salt from the market which is contaminated with Ammonium Chloride (NH4Cl ). Identify the technique that he should adopt to obtain pure NaCl.
Mix the sample in acetone and evaporate the decanted solution.
Ammonium Chloride is a substance which directly converts to its vapour upon heating, without forming a liquid state. This process is called sublimation. The vapours can be collected and condensed into a separate flask. On the other hand,NaCl does not get evaporated on heating and can be separated easily.