Naphthalene is insoluble in water but soluble in ether*. When this mixture is dissolved in water, naphthalene will remain insoluble and will be recovered at the bottom of the beaker. But it is volatile* at room temperature.
* Ether is an organic solvent that contains an oxygen molecule connected to two alkyl/aryl groups. Example: R-O-R^’ is an ether.
*Volatile: Any substance that can be easily evaporated at room temperature is called volatile substance.

Ammonium chloride is soluble in water and is volatile at higher temperatures i.e. it evaporates at higher temperature and not at room temperature. This mixture can then be decanted in the funnel fitted with filter paper. The filtrate then contains ammonium chloride dissolved in water. It decomposes on heating to dryness.