4.3.3.3 - Increasing the pressure of a gas

What does the pressure of gas cause to its container?

The pressure of a gas causes a net outward force at right angles to the surface of a container.

Explain how changes in pressure can lead to a container being compressed / expanded.

Pressure of a gas causing a net outward force at right angles to the surface of a container

Force outside the container due to the pressure of the gases around it

So if the container can easily change it’s size, then any changes in these pressures will cause the container to compress or expand

What is meant by ‘work’?

Work - the transfer of energy by a force

what increases if you do work on a gas?

Doing work on a gas increases the internal energy of the gas.

So, what does an increase in internal energy lead to?

Doing work on a gas increases the internal energy of the gas.

This can cause an increase in the temperature of a gas

Give an example of doing work on a gas mechanically.

E.g. with a bike pump

Explain how a bike pump does work.

The gas applies pressure to the plunger of the pump, so exerts a force on it

This means that work has to be done against this force to push down the plunger

This transfers energy to the kinetic energy store of the particles - increasing the temperature