Work calculation for isothermal compression

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Homework Statement


Physics homework screenshot: calculate work done by an external agent in isothermal compression of 1.00 mol oxygen from 24.0 L at 0°C and 9.37 × 10^-1 atm to 17.5 L; entered answer -716.95 J marked incorrect; prompt asks how isothermal work relates to initial and final volumes.



Homework Equations


Work done by an ideal gas, isothermal process: W=n*R*T*ln(V_f / V_i)
Work, constant-pressure process: W=p*(V_f - V_i)

The Attempt at a Solution


I first tried plugging n=1, R=8.31, T=273.15, V_f=17.5 L, V_i=24 L into the first equation and it didn't work.

I then tried the constant-pressure formula with the corresponding values given from the problem (p=.937 atm, V_f=17.5 L, V_i=24 L) and it didn't work either.

This problem seems pretty straight forward but I can't get the right answer. Help?
 
The work formula you used is for the work of the gas. The problem asks the work of an external agent. Is the external work positive or negative?

The data given are not consistent with the ideal gas law. 1 mol oxygen at 0 °C can not have 24 L volume at 0.937 atm pressure. Have you copied it correctly?

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