Steam distillation is the simplest method, which is used to isolate materials that are temperature sensitive like organic compounds. It is applicable at a low boiling point in order to avoid decomposition. It cannot be applicable in the purification of those organic compounds that are water soluble, non-volatile in steam, vapour pressure low and contains volatile impurities. p-nitrophenol is steam volatile, thus it cannot be used for purifying by steam distillation.