Question

Which of the following situations is it appropriate to perform a recrystallization?

a. To purify an impure liquid.
b. To purify an impure solid.
c. The melting point of a compound is depressed and melts over a wide range.
d. The melting point of a compound is sharp and agrees with the literature value.

Answer 1

Recrystallization is appropriate when trying to purify an impure solid, when the compound has a depressed melting point and melts over a wide range, or when the compound has a sharp melting point that agrees with the literature value.

Step-by-step explanation:

Recrystallization is a technique used to purify compounds by dissolving them in a hot solvent and then allowing them to crystallize out of solution upon cooling. It can be performed when:

1. The compound is an impure solid and needs to be purified.
2. The compound has a depressed melting point and melts over a wide range.
3. The compound has a sharp melting point that agrees with the literature value.

By recrystallizing, impurities can be removed, resulting in a more pure compound.