Calculate the value of S for the conversion of n = 1 molof liquid water at 100C

Question

Calculate the value of S for the conversion of n = 1 molof liquid water at 100C and 1 bar pressure into vapor at the sametermperature and a pressure of 0.01 bar. Assume idealbehavior for vapor. The molar enthalpy of vaporization ofwater at 100C and 1 bar is 40.0 kJ/mol. Please help with this problem. Had an exam and wasn'tclear on how was solved. Thanks alot.
This is what I got: S = nRln pi/pf = 1 mol X8.31451 JKmol ln (1 bar/0.01bar) = 38.29 JK Professor wrote that my result was for S1. Therefore, S2 needed to be calculated. Then,S1 +S2 would equal toS. Information he gave: S1for expansion and S2 for the liquid-gas transition, which isthe part I had trouble calculating to get the total S. Please help . Thank you. Calculate the value of S for the conversion of n = 1 molof liquid water at 100C and 1 bar pressure into vapor at the sametermperature and a pressure of 0.01 bar. Assume idealbehavior for vapor. The molar enthalpy of vaporization ofwater at 100C and 1 bar is 40.0 kJ/mol. Please help with this problem. Had an exam and wasn'tclear on how was solved. Thanks alot.
This is what I got: S = nRln pi/pf = 1 mol X8.31451 JKmol ln (1 bar/0.01bar) = 38.29 JK Professor wrote that my result was for S1. Therefore, S2 needed to be calculated. Then,S1 +S2 would equal toS. Information he gave: S1for expansion and S2 for the liquid-gas transition, which isthe part I had trouble calculating to get the total S. Please help . Thank you. Please help . Thank you.

Explanation / Answer

Yes your answer is not satisfying because here there are twotransitions as they had given vapour had ideal behaviour it isbetter to assume like this 1.Liquid-gas transition at same pressure 2. As vapour had ideal behaviour so expand it to final pressure (And they also given molar enthalpy at 1 bar)      s =s1+s2 For liquid gas transition H2 =40*1=40KJ which is justenthalpy of vaporization. Then entropy s2=40/373 =107.23 J Add up and get theanswer Best answer dude

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