Impure benzoic acid was dissolved in hot water. the container of solution was placed in an ice-water bath instead of being allowed cooling slowly .what will be the result of cooling the solution in this manner

The result of cooling in this manner is that impurities will be removed from the impure benzoic acid resulting in a more purified benzoic acid. The method described above is known as re-crystallization and it is often used to remove impurities from substance by choosing conditions that will favour the re-crystallization of the substance only, thus leaving the impurities behind. 

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