Separation of Naphthalene and Benzoic Acid

1. Sublimation:
- Naphthalene can be separated from benzoic acid by sublimation. When the mixture is heated, naphthalene sublimes, meaning it changes directly from a solid to a vapor without passing through the liquid phase, leaving behind the benzoic acid.

2. Solvent Extraction:
- Another method is solvent extraction. In this process, the mixture is dissolved in a suitable solvent. Since benzoic acid is soluble in organic solvents while naphthalene is not, the benzoic acid can be extracted from the solution by adding an organic solvent. The naphthalene will remain undissolved.

3. Acid-Base Extraction:
- Acid-base extraction can also be used to separate naphthalene and benzoic acid. Since benzoic acid is acidic, it can react with a base such as sodium bicarbonate to form a water-soluble salt. Naphthalene, being non-acidic, will remain unaffected. The two components can then be separated by filtering the mixture.

4. Chromatography:
- Chromatography can also be employed to separate naphthalene and benzoic acid. By using a chromatographic column packed with a suitable stationary phase, the components can be separated based on their different affinities for the stationary phase.

Overall, the choice of method for separating naphthalene and benzoic acid would depend on factors such as the purity required, the quantity of the mixture, and the availability of equipment and solvents. Each method has its advantages and limitations, and the most suitable one should be chosen based on the specific requirements of the separation process.

Ans: Crystallisation