# Determine the work done by the gas

1. Sep 16, 2008

### yossup

1. The problem statement, all variables and given/known data

A 1.10 mol sample of an ideal diatomic gas at a pressure of 1.20 atm and temperature of 420K undergoes a process in which its pressure increases linearly with temperature. The final temperature and pressure are 720K and 1.83atm.

Determine the work done by the gas.

Determine the heat added to the gas.

2. Relevant equations

E= 5/2 nRT

3. The attempt at a solution

So the change in internal energy I calculated to be 6860J.

So W + Q = 6860.

I can't figure out how to calculate W or Q because I don't know what kind of process this is (adiabatic, isobaric, isochoric, etc.) It just says pressure increases linearly with temperature. :(

2. Sep 16, 2008

### Ygggdrasil

Re: thermodynamics

Think of the ideal gas equation. If pressure increases linearly with temperature, what does that tell you about the process.

3. Sep 17, 2008

### yossup

Re: thermodynamics

isochoric! :D

4. Sep 17, 2008

### Ygggdrasil

Re: thermodynamics

Exactly. That make's the subsequent calculations really easy :)

5. Sep 17, 2008

### yossup

Re: thermodynamics

if it's isochoric, the work done by the gas should be zero but it says i'm wrong so it isn't isochoric?

6. Sep 17, 2008

### Ygggdrasil

Re: thermodynamics

Something's wrong with the problem. It says P increases linearly with T, but P_1/T_1 is not equal to P_2/T_2.

7. Sep 18, 2008

### yossup

Re: thermodynamics

isn't that because it's not at constant volume?

P1/T1 = P2/T2 only at constant volume... :(

8. Sep 19, 2008

### Ygggdrasil

Re: thermodynamics

But if P increases linearly with T then P = c T, where c is a constant, so P/T = c implying that P_1/T_1 = P_2/T_2