An engine runs on a rich mixture of methyl and ethyl alcohol and air. At a pressure of 1 bar and \(10^{\circ} \mathrm{C}\) the fuel is completely vapourised. Calculate the air-fuel ratio by volume under these conditions, and the percentage of ethyl alcohol in the fuel by weight. If the total pressure of the exhaust gas is \(1 \mathrm{bar}\), calculate the dew point of the water vapour in the exhaust and the percentage by volume of carbon monoxide in the dry exhaust gas assuming all the hydrogen in the fuel forms water vapour.

Vapour pressures at \(10{ }^{\circ} \mathrm{C}\) : methyl alcohol \(\left(\mathrm{CH}_{3} \mathrm{OH}\right), 0.0745\) bar; and ethyl alcohol \(\left(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\right), 0.310\) bar.

[ \(63{ }^{\circ} \mathrm{C} ; 4.15 \%\) ]