The gas laws
include Boyle's Law
, Charles' Law
and Graham's Law
and describe the relationship between temperature
of gases. They are collectively generalized by the universal gas equation
, also known as the ideal gas law
A gas which obeys gas laws exactly is hypothetical, and is known as an ideal gas (or perfect gas).
Boyle's Law, named after Robert Boyle, states that the volume occupied by a gas at constant temperature is inversely proportional to the pressure applied. In other words,
Charles Law, named after Jacques Charles
, states that the pressure that a gas exerts on the walls of its container is determined by the momentum
of the atoms
of the gas, which in turn is determined by the temperature. As the temperature increases the atoms and molecules move faster, and so exert a greater pressure on the walls. If the walls are rigid, such that the volume of the container is held constant, then the relationship between pressure P and temperature T is given by Charles' Law:
Graham's Law, named after Thomas Graham
, states that the kinetic energy
of two samples of different gases at the same temperature is identical.