Explanation:
Recrystallization is based on the principle that solubility increases with increase in temperature. It a method of purifying a compound in an appropriate solvent.
In this method impure compound is dissolved in the solvent at high temperature. After that solution is cooled slowly. During cooling, the compound crystallizes and impurity remains in the dissolved state.
In the given situation, water/ethanol is used as a solvent. Weight of compound after recrystallization is more. This is because the alkyl ether obtained after recrystallization was not completely dried. extra amount is because of water present in it.
Therefore, dry it and reweigh for the correct amount of alkyl ether.
