Question

Given that naphthalene is insoluble in water and sublimes easily upon heating, describe two different methods by which you could separate naphthalene and Nacl.

Answer 1

Based on solubilities you can separate naphthalene and NaCl by adding the mixture to a volume of water. NaCl is highly soluble in water, so it will dissolve completely, while the insoluble naphthalen will remain solid. Next your filter the solution, washing the solid with pure water to eliminate all the NaCl from it. The NaCl will remain is solution, and you can obtain it by evaporating the water. The other method to separate naphthalene and NaCl is based on sublimation property of naphthalene: you can permit that naphthalene sublimes freely or use vacuum to accelerate the process. You use a closed vessel to catch all the gas, while the NaCl will remain solid.