states that pressure is indirectly proportional to volume when the temperature and moles of the gas are constant.
This relationship can be modelled by the equation:
##P_1V_1=P_2V_2##
where:
##P_1=##initial pressure
##V_1=##initial volume
##P_2=##final pressure
##V_2=##final volume
When pressure is indirectly proportional to volume this means that
say for example if the pressure was increased by a factor the volume would decrease by the ##color(red)(same)## factor.
Similarly if the volume was increased by a factor the pressure would decrease by the ##color(red)(same)## factor.
For example if the initial pressure was ##color(blue)2## ##color(blue)(atm)## the initial volume was ##color(blue)4## ##color(blue)L## and the pressure decreased by a factor of ##color(blue)(1/2)## the volume would increase by a factor of ##color(blue)2##.
Algebraically we can solve for the final volume using Boyle’s Law formula assuming that the temperature and moles of the gas are constant:
##P_1V_1=P_2V_2##
##(2atm)(4L)=(1atm)(V_2)##
##V_2=((2color(red)cancelcolor(black)(atm))(4L))/((1color(red)cancelcolor(black)(atm)))##
##V_2=8## ##L##
Thus the volume has increased from ##4## ##L## to ##8## ##L##.
Graphically the relationship between pressure and volume can be represented as: