8.113

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Leah Savage 2F
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Joined: Fri Sep 29, 2017 7:06 am

8.113

Postby Leah Savage 2F » Tue Jan 23, 2018 11:13 pm

8.113 says: Water gas is an inexpensive, low-grade fuel that can be made from coal. (a) Is the production of water gas exothermic or endothermic? The reaction is C (s) + H2O (g) --> CO (g) + H2
(b) Calculate the enthalpy change for the production of 200. L of hydrogen at 500. Torr and 65 C by this reaction.

Can someone explain why the solutions manual uses 0 for the value of the enthalpy of formation for C(s) to find the enthalpy of the reaction? Isn't the standard state of carbon (gr)?

Andrea Grigsby 1I
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Re: 8.113

Postby Andrea Grigsby 1I » Tue Jan 23, 2018 11:46 pm

what does the state (gr) mean?

torieoishi1A
Posts: 32
Joined: Sat Jul 22, 2017 3:00 am

Re: 8.113

Postby torieoishi1A » Wed Jan 24, 2018 9:48 am

the state gr means graphite. It is the most stable form of carbon under standard conditions.

Austin Ho 1E
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Re: 8.113

Postby Austin Ho 1E » Wed Jan 24, 2018 10:15 am

I think in this question when they say C(s) they're specifying that it's solid carbon and not necessarily graphite. Therefore, its formation enthalpy is 0.


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