Naphthalene can be easily purified by:A.Sublimation B.CrystallizationC.DistillationD.Extraction with a solvent

To determine how naphthalene can be easily purified, let’s analyze each option:

A. Sublimation
Explanation: Sublimation is a process where a solid transitions directly into a gas without passing through the liquid phase. Naphthalene, when heated, sublimates at a temperature around 80 °C. This property can be utilized to purify naphthalene, as impurities would generally not sublimate and would remain behind. The naphthalene gas can then be condensed back into solid form, effectively separating it from non-volatile impurities.
Conclusion: This method is effective for purifying naphthalene.
B. Crystallization
Explanation: Crystallization involves dissolving a solid in a solvent and then allowing it to reform as crystals as the solution cools or evaporates. Naphthalene can be purified this way, but it may not be as effective for all impurities, especially if they are soluble in the same solvent.
Conclusion: This method can be used but might not be as efficient as sublimation.
C. Distillation
Explanation: Distillation is used to separate components based on differences in boiling points. While naphthalene has a defined boiling point (about 218 °C), this method would generally require more complex setups and may not be as straightforward for purifying solid naphthalene. It’s more commonly used for liquid mixtures.
Conclusion: Less effective for solid naphthalene.
D. Extraction with a solvent
Explanation: This method involves using a solvent to dissolve naphthalene, separating it from impurities based on solubility differences. While this can be effective, it might not always yield pure naphthalene since some impurities might also dissolve in the solvent.
Conclusion: This method can be used, but it’s not as straightforward as sublimation.
Final Conclusion
Among the given options, A. Sublimation is the most efficient and direct method for purifying naphthalene due to its unique physical properties, making it the best choice for this process.