Question

The enthalpy of combustion of gasoline (C8H18) is 5471 kJ mol-1. How much heat will be produced by burning 1 gallon of gasoline at 25°C? (Density of gasoline = 0.703 g/mL; 1gallon = 3.78 L) Show your work clearly.

Answer 1

Answer:

127529 KJ

Explanation:

Since 1gallon = 3.78 L= 3780 ml

The density of C8H18= 0.703 g/mL

Density = mass/volume

Mass= Density × volume

Mass= 0.703 g/mL × 3780 ml

Mass= 2657.34 g

Molar mass of C8H18= 114 g/mol

Number of moles= mass/molar mass

Number of moles= 2657.34/114

Number of moles= 23.31 moles

Since 1 mole evolved=5471 kJ

23.31 moles = 5471 kJ × 23.31 = 127529 KJ