1. The problem statement, all variables and given/known data [PLAIN]http://img821.imageshack.us/img821/8541/cheme.png [Broken] I am only looking for help in part a. 2. Relevant equations PV = mRT 3. The attempt at a solution By looking at the figure, I was able to calculate the volume of state 2, which is half of the volume of state 1. V1 = (mRT1)/P1 V1 = (5*0.287*573)/200 V1 = 4.11 meters cubed V2 = V1/2 V2 = 2.06 meters cubed However, in order to calculate the temperature by using the Ideal Gas Law, I need pressure first. How do I go about finding pressure? Is there an assumption I'm supposed to make first?