Question

Explain the sublimation and vaporization processes. How does the condensation process relate to vaporization and how does deposition relate to sublimation? Give an example of each process

Answer 1

Evaporation :

This is surface phenomenon. Molecules in the liquid are continuously moving. Their kinetic energy depends on temperature of the liquid. When this kinetic energy is higher than the attractive force between molecules, it start to break the intermolecular interactions in the liquid and molecule start leaving the liquid at the surface. This is called as evaporation.

Basically it is the process of conversion of liquid into vapour.

Water evaporates into the vapour when we heat it.

Sublimation:

There are some substances that are evaporates when they are in their solid phase. This process of conversion of solid directly to vapour without converting into liquid is called as sublimation.

Example: Camphor. When camphor is kept open it start to sublimate.

Condensation :

Molecules in the gaseous state have higher kinetic energy than that of the molecules which are in liquid state. When their temperature is lowered, kinetic energy is lowered and they start to feel interactions. This is because their kinetic energy unable to overcome their intermolecular force of attraction. When such intermolecular forces overcome the kinetic energy, gaseous molecule start to convert into liquid. This is the process which called as condensation.

In the distillation experiment we convert vapour to liquid by cooling the vapour in the condenser by using water tube.

Vapour condense to water droplet around the test tube can be observed.

Deposition :

The process in which gaseous molecules directly goes to the solid phase without conversion into liquid phase is called as deposition.

Sometimes water vapour also directly in winter months.