work question

[Doctor D]

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A piston is used to apply pressure to an ideal gas inside a cylinder. The gas is warmed from 0 celsius to 25 celsius at constant volume of 10 L. The pressure inside the cylinder increases by 1 atm. How much work is done on the gas?
A. 0 J
B 10 J
C. 250 J
D. 500 J

I cant figure out what formula I am missing here. any help?

 

[RPedigo]

I'm not good at physics, so hopefully someone more knowledgeable than myself chimes in. Assuming we only care about PV work, then...

w = -PΔV. The ΔV is zero, so the work should be zero.


Was 0J the answer?

 

[pheonix10]

0 should be the answer, due to the definition of work at constant volume

 

[cwfergus]

Yeah if its constant volume it SHOULD be 0.

 

[Doctor D]

I also thought the answer was 0 but examkrackers 1g exam says the answer is 250 J. typo?

 

[physics junkie]

The question is how much work is done on the gas. Not how much work is done by the gas. I agree with everyone else though that the work done in an isochoric process is 0. But let's see if I can find the examkrackers answer another way..

PV=nRT.

I'm not even sure if this is correct but:

take 8.314472 J/(K*mol) as the gas constant. You have 22.4L of gas per mole at STP.

so 8.314*(10/22.4)*25 = 94J ok that's incorrect sorry.

Check the examkrackers errata page to see if its listed there.