Problem: The table below shows the average bond energies for some common bonds among carbon, hydrogen, and oxygen.BondBond energy(kJ/mol)C - C347C - H414C - O360C = O799H - H436H - O464O - O142O = O498Calculate ΔHrxn for the combustion of octane by using enthalpies of formation from the transition above.

FREE Expert Solution

To calculate ΔHrxn using bond energies, we will use the following equation:


Write the combustion reaction of octane:

• Hexane is a a hydrocarbon composed only of carbon and hydrogen.
• The prefix oct- means 8 carbons.
• General Formula: CnH2n+2    where n = number of carbons
• Hexane: C8H18

Balanced Combustion reaction:

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Problem Details

The table below shows the average bond energies for some common bonds among carbon, hydrogen, and oxygen.

BondBond energy
(kJ/mol)
C - C347
C - H414
C - O360
C = O799
H - H436
H - O464
O - O142
O = O498


Calculate ΔHrxn for the combustion of octane by using enthalpies of formation from the transition above.

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