Boyle’s law, developed by English scientist Robert Boyle, states that:

*The smaller the volume a given amount of gas is squeezed into, the greater the pressure the gas exerts on the walls of its container. Boyle's law, a mathematical equation that more precisely describes this relationship, states that at constant temperature, the volume of a given quantity of gas varies inversely with the pressure exerted on it. Mathematically, this relationship can be expressed:*

V = k (1/P)

*where V is volume; k is Boltzmann’s constant (equal to 1.38 × 10-23 and named for the Austrian physicist Ludwig Boltzmann); and P is pressure. If the pressure on a given amount of gas is doubled, for example, its volume will decrease by one-half (as long as the temperature of the gas remains unchanged). Conversely, if the pressure is decreased by one-half, the volume will double.*