Question

Why do we feel cool after applying shave lotion or perfume?

Answer 1

Hint: Perfume and shave lotion contains spirit. And evaporation is a process in which liquid is converted into vapours. The conversion of one state of matter to another can be explained on the basis of energy transfer between the molecules when they collide with each other.

Complete step by step solution:
Let us first define states of matter.
There are mainly three states of matter known as: solids, liquids and gases.
Solids: Solids are those states of matter which have definite shape and definite volume. Fixed shape means if we place them in any container then their shape will not change. It will be the same as before.
Liquids: Liquids are those states of matter whose atoms or particles are held together by intermolecular force which is less than that of forces in solids.
 Gases: Gases are those states of matter whose atoms or particles are held together by a very weak force of attraction i.e. vanderwaal force of attraction which is less than that of forces in solids and in liquids. Gases do not have definite volume and do not have definite shape.
Evaporation: It is a process in which liquid is converted into vapours. The conversion of one state of matter to another can be explained on the basis of energy transfer between the molecules when they collide with each other. When we give heat to the system then they move faster and when they move fast in a system then they release heat and convert to another state.
Now, Perfume and shave lotion contain spirit. When we apply perfume or shave lotion to our body. Then by using the heat of the body spirit evaporates. And the boiling point of spirit is low that’s why spirit can easily undergo evaporation by the heat of the body also. As energy is released by our body so we feel cool after applying perfume or shave lotion.

Note: The conversion of solid to liquid is known as melting, conversion of solid to gas without going into liquid phase is known as sublimation, conversion of liquid to solid is known as freezing or solidification, conversion of liquid to gas is known as vaporization, conversion of gas to solid without going to liquid phase is de-sublimation and conversion of gas to liquid is known as condensation.