If a certain gas occupies a volume of 12 l when the applied pressure is 6.0 atm, find the pressure when the gas occupies a volume of 3.0 l.

From Boyle's law, the volume of a fixed mass of a gas is inversely proportional to its pressure at constant absolute temperature.

Therefore; P1V1 = P2V2; where PV is a constant

hence; 12 * 6 = 3 * p2

p2 = 72/3

= 24 atm

Therefore; the new pressure will be 24 atm