July 12, 2020, 08:33:43 AM
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Topic: thermo question-dont believe enough info given  (Read 2082 times)

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Offline taylor

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thermo question-dont believe enough info given
« on: April 04, 2009, 05:44:26 AM »
hey guys ive got a question ive never seen before. 
"carbon dioxide is produced in the combustion of carbon in the presence of oxygen. calculate the value of S0 for the oxidation of carbon as graphite to carbon dioxide: C (s, graphite)+02 >CO2
thanks for any help

Offline lancenti

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Re: thermo question-dont believe enough info given
« Reply #1 on: April 04, 2009, 05:47:19 AM »
S = q/T = -dH/T

q: Heat absorbed by the surroundings
T: Temperature of the surroundings
S: Entropy Change

So you'll need dHcombustion and using that you can work out the dS for the reaction.

Offline taylor

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Re: thermo question-dont believe enough info given
« Reply #2 on: April 04, 2009, 07:23:52 AM »
thanks for the reply but how do i work out dH? isnt there too many variables?

Offline lancenti

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Re: thermo question-dont believe enough info given
« Reply #3 on: April 07, 2009, 11:33:49 AM »
dH is basically the enthalpy change of the reaction. You can work this out using Bond Energies, since the energy released has to be the difference in bond energies (by Conservation of Energy)

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