Question

Substances that sublime can be made to liquefy by

• A. heating them under high pressure
• B. cooling them under high pressure
• C. heating them under very low pressure
• D. cooling them under very low pressure

Answer 1

The correct option is A heating them under high pressure

Sublimation is the process of conversion of a substance from solid state to gaseous state without entering the liquid state. When more pressure is applied, the gaseous particles would come closer and closer (because of compression) and tend to form liquids. The heat energy supplied under pressure will then force the solid to convert into liquid state, as now it cannot sublime due to the pressure applied over it.

Hence, Option "A" is the correct answer.