What type of distillation is most appropriate to separate a mixture of solvents with boiling points significantly apart (e.g. 45°C and 120°C)?

Simple distillation is the most appropriate method for separating a mixture of solvents with significantly different boiling points, such as 45°C and 120°C. This technique is based on the principle of vaporization and condensation; as the mixture is heated, the component with the lower boiling point (in this case, the solvent boiling at 45°C) will vaporize first.

During simple distillation, the vapor produced is cooled and condensed back into liquid form in a receiving flask, allowing the lower boiling solvent to be collected separately from the rest of the mixture. Since the boiling points of the solvents in this scenario are well-separated by a large margin, simple distillation proves effective; it can achieve a good separation without the need for the more complex setup required for fractional distillation.

Fractional distillation is more suitable for separating liquids with closer boiling points, as it uses a fractionating column to provide multiple vaporization-condensation cycles, enhancing the separation. Vacuum distillation is used for liquids that have high boiling points that may decompose at those temperatures, and steam distillation is typically applied for temperature-sensitive compounds with enough vapor pressure at lower temperatures. In cases like the one described, where there is a clear and significant difference in boiling points, simple