## Yahoo! 3 years ago A steel cylinder capacity 10L holds 20 Moles of O2 at 27 C an imperfection causes the gas to leak out slowly so that temperature remains Contant Ext Pressure is 1 atm The cylinder Finaaly Contain 1 atm Calculate Work Done in Calories

1. experimentX

this is isothermal process, work done is given by $n R T \log \left( V_b \over Va\right)\\ V_a = {10 \text{L}} \\ V_b = {300.4 \over 273.4}*20*22.4 \text{L}$

2. mahmit2012

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3. mahmit2012

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4. mahmit2012

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5. mahmit2012

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6. mahmit2012

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7. mahmit2012

I can't continue there is not Q ?

8. mahmit2012

Pay attention that in this case n is variable(leaking). so U is not constant(Adiabatic) So you can not find W(work) by int Pdv.

9. Vincent-Lyon.Fr

Is the answer 48.9 kJ = 11.7 Cal ?

10. mahmit2012

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11. mahmit2012

I think you should have how percent was leaked ?

12. Yahoo!

it is ~11700 cal @Vincent-Lyon.Fr

13. Yahoo!

@experimentX : $W=2.303*n*R*T* \log\frac{ P1 }{ P2 }$

14. Yahoo!

$P1 V = nRT$ $P1=~48atm$

15. Yahoo!

P2=1atm (given)......Can t we Do like this...?

16. experimentX

i guess you can.

17. Yahoo!

But Not getting the Correcr Result:

18. Yahoo!

but @Vincent-Lyon.Fr Got it correctly...)

19. Yahoo!

@Kryten

20. experimentX