# Gas Problem Assignment

1. Oct 25, 2009

### vortex193

1. The problem statement, all variables and given/known data
Container A holds an ideal gas at a pressure of 5x10^5 Pa and a temperature of 300 K. It is connected by a thin tube (and closed valve) to container B, with four times the volume of A. Container B holds the same ideal gas at a pressure of 10^5 Pa and a temperature of 400 K. The valve is opened to allow the pressures to equalize. What is the pressure in the two containers? Note: The temperatures in the containers do not go to an equilibrium and both temperatures stay at their original temperatures.

2. Relevant equations
PV = nRT (R = 8.31 J/mol*K)

3. The attempt at a solution
I have no idea how to do this.

2. Oct 26, 2009

### fantispug

A generally useful tip to start problems like this is to list mathematical expressions for your known information and what you are trying to work out. In this example we have two ideal gasses, so the variables are P,V,n and T for each vessel both before and after the valve has been opened. So write them down, like
Pressure (Vessel A, initial) = 5 * 10^5 Pa (Or more succinctly $$P_A^{i} = 5 \times 10^5$$ Pa).
Volume (Vessel A, initial) = x = Volume (Vessel A, final)
Volume (Vessel B, initial) = 4x = Volume (Vessel B, final).
.
.
.

Now concentrate on the unknown you're trying to find
P(A, final) = P(B, final)
using the ideal gas equation (maybe a couple of times) and the information given can you work out a solution?

Give it a go.