A container with a volume of #5# #L# contains a gas with a temperature of #360# #K#. If the temperature of the gas changes to #120# #K# without any change in pressure, what must the container's new volume be?

1 Answer
Feb 14, 2016

Start with the 'combined gas law': #(P_1V_1)/T_1=(P_2V_2)/T_2#. Pressure is constant, so we can ignore it and be left with #(V_1)/T_1=(V_2)/T_2#.
Rearranging, #V_2=(V_1T_2)/T_1=(5*120)/360=5/3# #L=1.67# #L#.

Explanation:

There are a number of different gas laws that link the pressure, temperature and volume of gases.

You could memorise Boyle's Law, Charles' Law and Gay Lussac's Law. I find it simpler, though, to just learn the Combined Gas Law that combines all of them, and then eliminate the things I don't need.

More understanding, less memory: my approach to learning physics. ;-)