Kinetic Theory

Key Stage 3

Meaning

Kinetic Theory is a theory that explains the properties of gases by the motion of the particles it is made from.

About Kinetic Theory

Kinetic Theory explains the properties of gases as such as the pressure, volume and Density.

Kinetic Theory can be used to explain the properties of a gas change depending on the temperature.

The higher the temperature of a gas the faster the particles in that gas and move.

Key Stage 4

Meaning

Kinetic Theory is a theory that explains the properties of gases by the motion of the particles it is made from.

Kinetic Theory and Pressure

Kinetic Theory explains how pressure is caused by the collision of particles with the walls of its container.

Pressure on the walls of the container is affected by how often the particles collide with the walls and fast they are moving when they do.

Increasing the temperature of a gas causes the particles to move faster making them hit the walls of the container harder and more often. This increases the pressure in the container.

Increasing the pressure on the walls of the container form outside can compress the gas into a smaller volume. When this happens work is done on the gas increasing its temperature.

Kinetic Theory and Volume

Kinetic Theory explains how the volume of a gas is affected by the temperature of a gas.

When a gas is not in a container or the container can change size then when the temperature increases and causes a pressure increase the gas will increase in volume.

Increasing the volume of a gas at constant temperature will decrease the pressure on the walls of the container because it takes the particles longer to move from one side of the container to the other. This means there will be less frequent collisions of the particles with the walls.