Question

If a substance decomposes if heated to its boiling point, suitable method is _____.

• A. simple distillation
• B. fractional distillation
• C. vacuum distillation
• D. crystallization

Answer 1

Answer: (C)

vacuum distillation

If a substance decomposes if heated to its boiling point, a suitable method is vacuum distillation. In vacuum distillation, the distillation is carried out at reduced pressure. The boiling point of the substance at reduced pressure is lower than the boiling point at atmospheric pressure. So the substance distills at a temperature which is much below its decomposition temperature.