Question

State True or False :

Vaporisation takes place only at boiling point.

• A. True
• B. False

Answer 1

The correct option is B False

False

Vapourisation can take place at any temperature but boiling can only take place at the boiling point. Since evaporation is a surface phenomenon. The reason of evaporation at any temperature is the molecules of a substance are always in motion.

When molecules near the surface of liquid get enough Kinetic Energy from internal motion collision or from surroundings, it can easily break the force of attraction from a lower level of molecules and escape to the atmosphere as the gas. The motion of molecules is zero near absolute zero temperature.

So, the liquid molecule can escape the surface at all temperatures.