Isooctane Is a Good Model Compound for Gasoline

Multiple Choice

Isooctane is a good model compound for gasoline. When 1.14 g of isooctane (114 g/mol) reacts with excess oxygen in a constant pressure calorimeter, the temperature of the calorimeter increases by 10.0^oC. The heat capacity of the calorimeter is 5.46 kJ/^oC. Determine the molar enthalpy of combustion of isooctane.

A) + 5,460 kJ/mol
B) +54.6 kJ/mol
C) -5,460 kJ/mol
D) -54.6 kJ/mol
E) -5.46 kJ/mol