Calculate Work Done on 1 Mole of Ideal Gas at Constant Pressure | 298K

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The discussion revolves around calculating the work done to compress 1 mole of an ideal gas from 1 atm to 0.5 atm at a constant external pressure of 1 atm and a temperature of 298K. The formula used for work done is Won = -Integral pdV, leading to a calculation of 2270J. There is confusion regarding whether temperature can be assumed constant during the process, as it typically changes with volume. Participants highlight a discrepancy in the problem statement regarding the use of volumes versus pressures. The conversation emphasizes the need for clarity in the problem's parameters to accurately determine the work done.
quietrain
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Homework Statement



calculate work done to compress 1mole of ideal gas from 1atm to 0.5atm at 298K
where it is subjected to constant external pressure of 1atm

Homework Equations


Won = -Integral pdV = -(1atm)(Vf-Vi) = -p(RT/pf - RT/pi) = 2270J

where i have assumed T does not change, is it correct to assume so?

because i read that T changes proportionally with V, if so, how do i find what is my (Vf-Vi)

thanks!
 
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quietrain said:

Homework Statement



calculate work done to compress 1mole of ideal gas from 1atm to 0.5atm at 298K
where it is subjected to constant external pressure of 1atm

Homework Equations


Won = -Integral pdV = -(1atm)(Vf-Vi) = -p(RT/pf - RT/pi) = 2270J

where i have assumed T does not change, is it correct to assume so?

because i read that T changes proportionally with V, if so, how do i find what is my (Vf-Vi)

thanks!
Are you sure that you have the question copied correctly. In particular, could you check that the two highlighted quantities should not be volumes?
 
yes that's what the question wrote

thats why i found it strange.

shouldn't it be vol, so that its just P(vf-vi)?
 
quietrain said:
yes that's what the question wrote

thats why i found it strange.

shouldn't it be vol, so that its just P(vf-vi)?
That would be my guess. There are two conflicting statements. The first specifies a change in pressure, whilst the second asserts a constant pressure.
 
ok thank you!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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