Boyle's law

The law, expressed in symbols, is:

PV = k

Where V is the volume of gas, P is its pressure, and k is a constant. The volume is expressed in cubic metres or litres and the pressure in pascals when using SI units.

To maintain the constant during an increase in pressure of a gas, at fixed temperature, requires that the volume decrease. Conversely, reducing the pressure of the gas increases the volume.

The exact value of the constant need not be known to make use of the law in comparison between two volumes of gas at equal temperature:

P₁V₁ = P₂V₂

Together with Charles law and Graham's law, Boyle's law forms gas laws, which describes the behaviour of an ideal gas. The three gas laws can be generalized by the universal gas equation.