Isothermal and reversible expansion work problem (Physical Chem)

AI Thread Summary
The discussion revolves around calculating the work (w) and heat (q) for the isothermal and reversible condensation of 2.00 mol of methanol at 64°C, given the standard enthalpy of condensation. Participants express confusion over how to determine the necessary volumes for the calculations, as the volume is not provided. Suggestions include using density assumptions to calculate the volume of liquid methanol and applying the ideal gas law for the gaseous state. There is also mention of considering the Van der Waals equation for more accurate results with real gases. The conversation highlights the challenges of finding appropriate formulas and values for this thermodynamic problem.
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Homework Statement


A sample of 2.00 mol. CH3OH (g) is condensed isothermally and reversibly to liquid at 64*C. The standard enthalpy of condensation of methanol @ 64*C is -35.3 kJ/mol. Find w and q for the reaction.


Homework Equations


w = -nRT * ln(Vf/Vi) (although I don't have volume so I don't know how to find it)


The Attempt at a Solution



Honestly I can't find any other reversible/isothermal condition work formulas to use. I am sure I am just missing how to calculate volume here. I have n, R, and T but am not given V. Not sure if this can be calculated?
 
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What is the volume of 2 mol of methanol at 64C? Make an assumption about it's density and calculate it (I assume you know how to convert moles to mass). Same thing goes for the volume of 2 moles of gas (methanol before condensation). The ideal gas equation might not be completely accurate but it is a good place to start.
 
Well, I am stuck on the same problem. I don't think that the ideal gas expression is the correct one... also, what do you get if you do 64 kJ/mol * 2 mol ? (I think this is the enthalpy for the reaction). And then, should you go back to the Van der waals equation for the real gas and implement that in your calculation of work ?
 
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