For which process will dH and dG be expected to be the most similar?
a)2Al(s) + Fe2O3(s) -> 2Fe(s) +2Al2O3(s)
b) 2Na(s) + 2H2O(l) -> 2NaOH(aq) + H2(g)
c) 2NO2(g) -> N2O4(g)
d) 2H2(g) + O2(g) -> 2H2O(g)
midterm 6 b
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Re: midterm 6 b
A, because the reaction has the smallest deltaS values, meaning in the equation deltaG = deltaH - TdeltaS, change in gibbs and change in enthalpy will be the closest to each other
Re: midterm 6 b
The states of matter hint at the answer, as all the products and reactants in answer choice a are solids.
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Re: midterm 6 b
For this problem, the answer would be the reaction that has the smallest change in entropy, which in this case is A.
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Re: midterm 6 b
since dG=dH-TdS, you want to find the smallest dS value. we see this in the first choice because the solid states remain most solid. hope this helps
Re: midterm 6 b
For deltaH and deltaG to be very similar, the change in entropy has to be minimal, so you would look to see which reaction has the least change in entropy, which would be A since the phase remains a solid throughout the reaction.
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Re: midterm 6 b
In order to solve this problem, you need to see which choice gives you an answer that has the smallest delta S. A would be the answer because that is the only one in which the state stays solid throughout, and solids have the lowest entropy values.
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