1. The problem statement, all variables and given/known data 2. Relevant 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) 3. 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?