# ideal gas law

The ideal gas law is a law relating the pressure (*P*), temperature (*T*), and volume
(V) of an ideal gas. Mathematically, the
ideal gas law can be written as:

*pV* = *nRT*,

where *n* is the number of molecules of the gas and *R* is the so-called gas constant.

The ideal gas law implies that at constant temperature (*T*), the
product of pressure and volume (*pV*) is constant (Boyle's
law) and at a constant pressure, the volume is proportional to the temperature
(Charles' law). See also equation
of state.