Isooctane Is a Good Model Compound for Gasoline

Multiple Choice

Isooctane is a good model compound for gasoline. When 1.14 g of isooctane (C₈H₁₈, molar mass  114 g/mol) reacted with excess oxygen in a constant volume calorimeter, the temperature of the calorimeter increased by 5.83C. The calorimeter consisted of two components: a steel vessel with a heat capacity of 1.00 kJ/C and 2.00 L of water surrounding it. The density and specific heat capacity of water are 1.00 g/mL and 4.184 J/(g  C) , respectively. Use these data to determine the molar enthalpy of combustion of isooctane.

A) (5.83 kJ)
B) (54.6 kJ)
C) (5,460 kJ)
D) (48,800 J)
E) (48,800 kJ)