Question

Find the heat of formation of carbon monoxide if the heat of combustion of carbon and carbon monoxide are -393 and -283kj/mol respectively.

Answer 1

C + O2 ==> CO2 dH = -393 kJ/mol = -393 kJ

2CO + O2 ==> 2CO2 dH = -283 kJ/mol x 2 = -566 kJ
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2C + 2O2 ==> 2CO2 dH = -393 kJ x 2 = -786 kJ
2CO2 ==> 2CO + O2 dH = +566 kJ
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2C + 2O2 ==> 2CO dH = -220 kJ/2 mol = -110 kJ/mol