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How to calculate the heat of formation of benzoic acid?Benzoic acid can be burned to...

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sweetskittles24 | Student, Grade 11 | (Level 1) Salutatorian

Posted October 23, 2012 at 4:18 PM via web

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How to calculate the heat of formation of benzoic acid?

Benzoic acid can be burned to produce liquid water and carbon dioxide. The molar enthalpy of combustion for benzoic acid is -3226.6 kJ/mol. 
2C6H5COOH (l) -> 6H2O (l) + 14CO2 (g) ΔH= -3226.6 kJ/mol

Given the heats of formation for liquid water is -285.5kJ/mol and carbon dioxide -393.5kJ/mol, calculate the heat of formation of benzoic acid.
I need full calculations for this question, please.

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jishnudeepkar | Student, Grade 11 | (Level 1) Honors

Posted October 24, 2012 at 4:24 PM (Answer #1)

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first div reaction by 2

C6H5COOH (l) -> 3H2O (l) + 7CO2 (g) ΔH= -1613.3 kJ/mol

ΔH(rxn)=3ΔH(h20)+ 7ΔH(co2) - ΔH(C6H5.....)

put values and solve ull get value of ΔH(C6H5.....)

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jishnudeepkar | Student, Grade 11 | (Level 1) Honors

Posted October 24, 2012 at 4:26 PM (Answer #2)

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-1613.3= -3611 - ΔH(C6H5.....)

ΔH(C6H5.....)= -3611+ 1613.3        .................

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