Sublimation cannot be used for purification of _______.

Sublimation is the transition of a substance from its solid to its gaseous state without passing through a liquid phase.

When a chemical compound is heated, sublimation occurs directly, without first passing through the liquid stage.

This method is mostly employed to extract contaminants from volatile organic molecules.

Anthracene, camphor, benzoic acid, and naphthalene are other examples.

Due to the fact that urea is not a volatile organic chemical, this approach is not used for it.