Combined gas law

The combined gas law is a thermodynamic variable to another mathematically while holding everything else constant. Charles's law states that volume and temperature are directly proportional to each other while pressure is held constant. Boyle's law asserts that pressure and volume are inversely proportional to each other at fixed temperature. Finally Gay-Lussac's law introduces a direct proportionality between temperature and pressure at constant volume. The inter-dependence of these variables is shown in the combined gas law, which states that:

This can be stated mathematically as

where:

P is the pressure,

V is the volume,

T is the (absolute) temperature,

C is a constant (with units of energy divided by temperature).

For comparing the same substance under two different sets of conditions, the law can be written as:

The addition of ideal gas law.