Pressure in a closed container changes if
temperature changes
number of molecules increases or decreases
volume changes
Boyle’s Law deals with number 3; the relationship between volume and pressure when the other two remain constant.
According to Boyle’s Law, the amount a gas will compress is proportional to the pressure applied. Its mathematical expression is:
P1V1=P2V2
Where, P1 is the pressure of a quantity of gas with a volume of V1 and P2 is the pressure of the same quantity of gas when it has a volume of V2. This means that if nothing else changes, the volume of a given mass of gas is inversely proportional to pressure it is under. It is a linear relationship. If pressure on a gas doubles, its volume will decrease by 1/2. An alternative expression of the law is:
PV = C
The product of the volume and pressure equals a constant.