8.117

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Ekayana Sethi 2K
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8.117

Postby Ekayana Sethi 2K » Sat Feb 10, 2018 11:27 am

what is the delta(n)? I thought it was 2 but the solutions manual says it is 2/3 why is that?

Manvir2K
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Re: 8.117

Postby Manvir2K » Sat Feb 10, 2018 4:52 pm

The net mole is 2 (4 on products side-2 on reactants side), but you only want one mole of H2. So then you divide it by 3 to get 1 mole of H2. Because of that, change in moles is 2/3 (I think).

Angela 1K
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Re: 8.117

Postby Angela 1K » Tue Feb 13, 2018 4:18 pm

Yes, that's correct. Because the equation is asking for the internal energy for the production of 1.00 mol H2, you should divide the entire equation by 3 in order to get 1 as a coefficient of H2 on the right-hand side.

Thus, your equation becomes
1/3 CH4(g) + 1/3 H2O(g) --> 1/3 CO2(g) + H2(g)
Your should be 4/3 - 2/3 = 2/3


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