Kinetic Theory

All collisions are elastic (no kinetic energy is lost)...

Kinetic energy of the gas is proprtional to the temperature of the sample...

There are negigible intermolecular forces...

Molecules are in constant random motion...

Molecules are small and the volume of molecules in negligible compared to the volume of the gas.

PV=nRT

8.31 J/K/mol or...

0.0821amt/dm³/K/mol

Pressure is inversely proportional to volume at constant temperature.

P₁V₁=P₂V₂

Volume is directly proportional to temperature at constant pressure

V₁/T₁=V₂/T₂

The partial pressure of a component gas is equal to the pressure it would exert if it alone occupied the total volume. The partial pressure of a gas is related to the number of moles of gas in the system.

p=mole fraction x total pressure

amount of component A / total amount

no. of moles A / total no. of moles

volume of A / total volume

At high temperatures and low pressure.

At high temperature, kinetic energy increases and intermolecular forces break and become negligible...

At low pressure, the distance between molecules increase and intermolecular forces become negligible. The volume of the molecules compared to the volume of the gas also becomes negligible.

The molecules have small but finite volumes and considerable intermolecular forces.

Above the line, the volume of the molecules compared to the gas is increasing as P increases. So the product PV is large due to the effects of volume.

Below the line, P is small due to the strong intermolecular forces between molecules so the product PV is smaller