If a gas has a volume of 1 l at a pressure of 270 kpa, what volume will it have when the pressure is increased to 540 kpa? assume the temperature and number of particles are constant.

The answer would be: 0.5L

This question can be solved using the ideal gas formula PV=nRT where
P= pressure
V= volume
n= number of molecule
R= constant
T= temperature

In this question, the temperature and number of the particle are not changed. The pressure is changed to twice amount. Since the pressure is inversely related to the volume, the volume should become half of the original.
PV=nRT 
V=nRT/P
V1/V2= (nRT/P1)/(nRT/P2)
V1/V2= (1/270)/(1/540)
V1/V2= (1/1)/(1/2)
V1/V2 = 2
V1= 2V2
1L= 2V2
V2= 1/2 L

Graph a should be your answer