(i) Calculate the specific energy of the lithium ion battery, in MJ kg⁻¹, when 80.0 kg of fuel in the battery releases 1.58 × 10⁷ J. Use section 1 of the data booklet.

(ii) The specific energy of gasoline is 46.0 MJ kg⁻¹. Suggest why gasoline may be considered a better energy source than the lithium ion battery based on your answer to part (a) (i).

(i) The energy density of gasoline is 34.3 MJ dm⁻³. Calculate the volume of gasoline, in dm³, that is equivalent to the energy in 80.0 kg of fuel in the lithium ion battery. Use section 1 of the data booklet.

(ii) The efficiency of energy transfer by this lithium ion battery is four times greater than that of gasoline. Determine the distance, in km, the car can travel on the lithium ion battery power alone if the gasoline-powered car uses 1.00 dm³ gasoline to travel 32.0 km.

i
«\(\frac{{1.58 \times {{10}^7}{\rm{J}}}}{{80.0{\rm{kg}}}}\)=\(\frac{{15.8{\rm{MJ}}}}{{80.0{\rm{kg}}}}\)=» 1.98 × 10⁻¹ «MJ kg⁻¹»

ii
gasoline releases more energy from a given mass of fuel
OR
gasoline has higher specific energy
Do not accept volume in place of mass as question refers to specific energy, not energy density.

i
«\(\frac{{15.8\,{\text{MJ}}}}{{34.3\,{\text{MJ}}\,{\text{d}}{{\text{m}}^{ - 3}}}}\)»= 4.61 × 10⁻¹ «dm³»

ii
«4.61 × 10⁻¹ dm³ × 32.0 km dm⁻³ × 4»= 59.0/59.1 «km»