Concept:Sublimation is the process where a solid changes directly into gas without passing through the liquid phase.
Explanation:Ammonium chloride (
NH4​Cl) sublimes when heated, converting into ammonia and hydrogen chloride gases.
Sodium chloride (
NaCl) does not sublime; it remains as a solid at the same temperature.
On heating the mixture, ammonium chloride turns into vapour and leaves sodium chloride behind.
The vapours can be collected and cooled to get back solid ammonium chloride.
Thus, the two solids are separated easily by this method.
Filtration works for solids in liquids, not for two solids.
Chromatography separates dissolved components based on affinity, not suitable here.
Distillation separates liquids with different boiling points, not solids.
Answer:sublimation