SayitIsntSO

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I thought when you are finding the change in enthalpy for a rxn you go: pdt-reactants? I am confused by the topscore solution in which you gotta find the change in enthalpy for: 2C(s)+O2(g)---> 2CO (g). I would try to rewrite the question, but it's too hard. For anyone who has topscore, i think you know this question. It is on test 2 for genchem, I think question 57 (gchem 17). I would really appreciate the help.
 

dat_student

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SayitIsntSO said:
I thought when you are finding the change in enthalpy for a rxn you go: pdt-reactants? I am confused by the topscore solution in which you gotta find the change in enthalpy for: 2C(s)+O2(g)---> 2CO (g). I would try to rewrite the question, but it's too hard. For anyone who has topscore, i think you know this question. It is on test 2 for genchem, I think question 57 (gchem 17). I would really appreciate the help.
If you post the question I may be able to help :) I don't have TOPSCORE
 

Pdiddy310

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SayitIsntSO said:
I thought when you are finding the change in enthalpy for a rxn you go: pdt-reactants? I am confused by the topscore solution in which you gotta find the change in enthalpy for: 2C(s)+O2(g)---> 2CO (g). I would try to rewrite the question, but it's too hard. For anyone who has topscore, i think you know this question. It is on test 2 for genchem, I think question 57 (gchem 17). I would really appreciate the help.
I could be wrong b/c it's been several years since I've taken gen chem but...

If I remember correctly, the heat of formation of elements in standard state is 0. Depending on whether or not the C(s) is diamond or graphite in this question, you will get a different answer.

The equation should look like this:

[2 x enthalpy of CO] - [2 x enthalpy of C(s) + 0]
 
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R.L.H

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Pdiddy310 said:
I could be wrong b/c it's been several years since I've taken gen chem but...

If I remember correctly, the heat of formation of elements in standard state is 0. Depending on whether or not the C(s) is diamond or graphite in this question, you will get a different answer.

The equation should look like this:

[2 x enthalpy of CO] - [2 x enthalpy of C(s) + 0]
i think you are right, b/c the heat of formation of elements in standard state (O2 (g) in this case) is 0.
 

dontbam

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SayitIsntSO said:
I thought when you are finding the change in enthalpy for a rxn you go: pdt-reactants? I am confused by the topscore solution in which you gotta find the change in enthalpy for: 2C(s)+O2(g)---> 2CO (g). I would try to rewrite the question, but it's too hard. For anyone who has topscore, i think you know this question. It is on test 2 for genchem, I think question 57 (gchem 17). I would really appreciate the help.
g
 
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