A type of fuel used in a spark ignition engine can be approximated as

having the chemical formula of $C_6{H}_{20}.$

The properties of $C_2{H}_{20}$ to be used for this question are:

Enthalpy of Combustion

$47\mathrm{.}8M\frac{J}{k}g$

Molecular Mass

$128k\frac{g}{k}$mol

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:

Questions a$),$ b$),$ c$)$ and d$)$ are as follows:

a$)$ Derive the balanced combustion equation for $C_2{H}_{20}$ 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.

i$.$ Derive the balanced combustion equation for the fuel $C_9{H}_{20}$

burning in a stoichiometric quantity of air.

ii$.$ Calculate the adiabatic flame temperature rise for the fuel

$C_9{H}_{20}$ burning in a stoichiometric quantity of air.

c$)$ Derive the balanced combustion equation for burning $C_9{H}_{20}$ 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$).$