See also Equations of State
Ideal Gas Law
PV = nRT
which states that pressure, P, and volume, V, is equal to the amount of the material, n, multiplied by the temperature, T, and a constant, R.
Using SI units, the pressure is expressed in pascals, the volume in liters, the amount in moles and the temperature in degrees Kelvin.
The ideal gas law incorporates both Charles Law and Boyles Law.