Motor Fuels Are Mixtures of Hydrocarbons, but They Can Be

Essay

Motor fuels are mixtures of hydrocarbons, but they can be characterized by their average properties. Gasoline (114 g/mol average, d = 0.69 g/mL) and diesel fuel (226 g/mol average, d = 0.85 g/mL) have average enthalpies of combustion of 5,650 kJ/mol and 10,200 kJ/mol, respectively. Calculate the fuel density (kJ/mL) of these compounds, and determine how many times more valuable diesel fuel is in terms of its energy content as measured by fuel density.