A type of fuel used in a spark ignition engine can be approximated as having the chemical formula of CH20. The properties of CH20 to be used for this question are: Enthalpy of Combustion 47.8 MJ/kg Molecular Mass 128 kg/kmol In addition, for the questions requiring the properties of air, the composition of air in this question should be taken as 79% Nitrogen and 21% Oxygen. The properties of the following liquids and gases to be used as required are: Product Formula Heat capacity Molecular mass kJ/kmol K kg/kmol Carbon CO 37.35 44.01 dioxide Water HO 33.80 18.02 Nitrogen N 29.9 28.01 Oxygen 02 32.00 32.00 Questions a), b), c) and d) are as follows: a) Derive the balanced combustion equation for CaH20 burning in a stoichiometric quantity of pure oxygen. b) In practice fuel in an internal combustion engine is burnt in air rather than pure oxygen. Derive the balanced combustion equation for the fuel CoH20 burning in a stoichiometric quantity of air. Calculate the adiabatic flame temperature rise for the fuel C9H20 burning in a stoichiometric quantity of air. c) Derive the balanced combustion equation for burning CoH20 with 25% excess air. d) State the Equivalence Ratio for an engine running with 25% excess air. e) Explain the difference between the Lower Calorific Value and the Higher Calorific Value of a fuel. (Note that the Calorific Value is also known as the Heating Value and the Enthalpy of Combustion).