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pentazoid
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Homework Statement
Suppose you have a mole of water at 198 K. and atmospheric pressure. use the data at the bac of this book to determine what happens to its gibbs free energy if you raise the temperature to 303 Kelvins. To compensate for this change, you could increase the pressure of the water. How much pressure would be require?
Homework Equations
V=(dG/dP), N and T are fixed
S=-(dG/dT), N and P are constant
delta(G)=delta(H)-Tdelta(S)
The Attempt at a Solution
H2O=> H2+.5*O2
delta(G)=-237.13 kJ/mol at 298 K(from thermodynamic reference table in back of my textbook).
I don't think I can used the equation delta(G)=delta(H)-Tdelta(S) since the temperature now changes ; therefore I turn to the equation S=-(dG)/dT. dT=303K-298 = 5 Kelvins. Not sure how to find
for the second part of the problem, I am now concerned with the amount of pressure I would add to compensate for the change in Gibbs free energy when the temperature increases. I think I would used the thermodynaimic identity equation , V=dG/dP? I would already have calculated dG from my equation S=-(dG/dT). How would I calculate my volume?