To separate any mixture into its components, we need to find a property to which they behave differently. In this case, solubility property of naphthalene and ammonium chloride can be considered.
We will use the fact that ammonium chloride is a highly soluble salt while naphthalene is insoluble in water. Do the following:
1. Take the mixture in a beaker and add water to it.
2. Stir the mixture in water for 10 minutes so that all the ammonium chloride is dissolved in water.
3.Now filter it using filter paper and funnel. Collect the filtrate in a beaker.
4. Now you have naphthalene on the filter paper and solution of ammonium chloride in water.
5. Collect the naphthalene from filter paper. Now you got one component of the mixture, that is naphthalene.
6. Take the filtrate in the beaker and evaporate the water carefully. After all the water is evaporated, the ammonium chloride will be left behind. Now you got the other component of the mixture, that is ammonium chloride.
Hence, you separated both components of the mixture.