Textbook Problem 4.7  [ENDORSED]

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Ryan Khiev 1L
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Textbook Problem 4.7

Postby Ryan Khiev 1L » Mon Jan 24, 2022 9:57 pm

Screen Shot 2022-01-24 at 9.54.45 PM.png


Can someone run through this problem? I keep getting the wrong answer and I don't know why. From Appendix 2A, I get [6(-393.52kJ) + 3(-241.82kJ)] - 49kJ = -3135.52 kJ, but the book says the answer is -3267.5 kJ. Also, I don't understand how to do part C. Thanks you in advance!

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Re: Textbook Problem 4.7  [ENDORSED]

Postby Chem_Mod » Wed Jan 26, 2022 1:49 pm

Delta U = qp + w

qp = Delta H

w = -P Delta V

Using PV = nRT one obtains: P Delta V = Delta n RT

Therefore, Delta U = Delta H - Delta n RT

Here are the numbers:
4.7.png


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