Charles' Law

Charles' Law can be explained by the kinetic theory of gases.

When the temperature of a gas is raised, the gas molecules will move more actively and with more energy.

The rate of collision of the gas molecules onto a unit area of the wall of the container will increase.

Each collision will also produce a greater force because the change in momentum for each molecule increases when its speed is higher.

To maintain the same pressure in the container, the volume of the gas will increase so that the above effects will be balanced by the effect of an even smaller number of molecules per unit.

Charles' Law states that for a mass of gas held at a fixed pressure, the volume of the gas is directly proportional to the absolute temperature of the gas.

According to Charles' Law

V1/T1 = V2/T2

V1 = initial volume
v2 = final volume
T1 = initial temperature in Kelvin
T2 = final temperature in Kelvin