Question

What is vaporization?

Answer 1

Hint: A liquid changes into its vapor form at a temperature equal to its boiling point by a process known as vaporization. For example, water converts to water vapor by the process of vaporization.

Complete step-by-step answer:

When a liquid attains enough energy from its surroundings in the form of heat or other forms of mechanical energy, it starts to convert into its vapor form. This is also known as the phase change from liquid to vapor form. This process is known as vaporization.
Vaporization is of two kinds - Boiling and evaporation.
In boiling the whole bulk of the liquid undergoes the phase change at a specific temperature known as the boiling point of the liquid. It is a bulk phenomenon, that is, the whole bulk of the liquid boils together.
In evaporation, some molecules on the surface of the liquid undergo the phase change at a temperature below the boiling point. This happens as the molecules on the surface can absorb energy from the outside surroundings. It is a surface phenomenon, that is only molecules on the surface of the liquid undergo evaporation.

Additional information:
As heat energy is required for the conversion of a liquid to its vapor form at its boiling temperature, it absorbs heat from its surroundings. The quantity of heat required is different for different liquids and is known as the latent heat of vaporization.
The enthalpy of vaporization is a function of the pressure in the surroundings of the liquid. As the pressure increases, the latent heat of vaporization also increases.

Note: Students must remember that the process of the phase change from liquid to vapor is known as vaporization and it can happen at temperatures below the boiling point also. Sometimes, students are tempted to believe that only boiling refers to vaporization and forget about evaporation completely and think that below the boiling point, vaporization is impossible. However, evaporation occurs at temperatures below the boiling point also.