When a 3.10g sample of liquid octane (C8H18) is burned in a bomb calorimeter, the temperature of the calorimeter rises by 26.8∘C. The heat capacity of the calorimeter, measured in a separate experiment, is 6.30kJ/∘C . Determine ΔErxn for the combustion of octane in units of kJ/mol octane.

Answer 1

http://www.chem.hope.edu/~polik/Chem345-2000/bombcalorimetry.htm

Read the above and see if you would do
dE = -CvdT
dE = -(6.30)(26.8) = kJ for (3.10/molar mass C8H18). Convert that to kJ/mol.

Answer 2

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