What is a recrystallization solvent?

What is a recrystallization solvent?

• A. A solvent in which the desired solute has low solubility at low temperatures and high solubility at high temperatures
• B. A solvent that completely dissolves all solutes at any temperature
• C. A solvent that has no effect on solubility
• D. A solvent that does not evaporate at room temperature

Answer: (A)

A recrystallization solvent is defined primarily by its ability to selectively dissolve the desired solute, facilitating the purification process. The effective solvent for recrystallization exhibits the characteristic of having low solubility for the solute at lower temperatures and high solubility at elevated temperatures. This property is crucial because it allows for the solute to be fully dissolved in the hot solvent, enabling the formation of a supersaturated solution. Upon cooling, the solute's decreased solubility leads it to crystallize out of the solution while impurities remain dissolved, thus achieving purification. The first option encapsulates this principle effectively, clearly stating that the desired solute has a low solubility at low temperatures and high solubility at high temperatures. This temperature dependency is the cornerstone of the recrystallization technique, allowing for successful isolation of pure crystals from a mixture. This definition emphasizes the importance of temperature in the recrystallization process and underlines why option A accurately represents what a recrystallization solvent should be.

A recrystallization solvent is defined primarily by its ability to selectively dissolve the desired solute, facilitating the purification process. The effective solvent for recrystallization exhibits the characteristic of having low solubility for the solute at lower temperatures and high solubility at elevated temperatures. This property is crucial because it allows for the solute to be fully dissolved in the hot solvent, enabling the formation of a supersaturated solution. Upon cooling, the solute's decreased solubility leads it to crystallize out of the solution while impurities remain dissolved, thus achieving purification.

The first option encapsulates this principle effectively, clearly stating that the desired solute has a low solubility at low temperatures and high solubility at high temperatures. This temperature dependency is the cornerstone of the recrystallization technique, allowing for successful isolation of pure crystals from a mixture.

This definition emphasizes the importance of temperature in the recrystallization process and underlines why option A accurately represents what a recrystallization solvent should be.