Methane enters an old furnace at a rate of $300\mathrm{.}0k\frac{g}{h}.$ It is accompanied by $31\mathrm{.}0\%$ excess air containing $0\mathrm{.}959$ mol$\%$ water and the

remainder a $3\mathrm{.}76$:$1$ molar ratio of $N_2$ to $O_2.$ Mixing of the combustion gases is very poor so that incomplete combustion is significant.

The combustion reactions proceed according to

$C{H}_4+2O_{2}C{O}_2+2H_{2}O$

$C{H}_4+\frac{3}{2}{O}_{2}CO+2H_{2}O$

Take the stoichiometric coefficients to have units of kmoles.

A significant amount of uncombusted methane leaves the furnace. The exhaust gas contains $1\mathrm{.}71wt\%CO$ and $0\mathrm{.}54wt\%C{H}_4,$ on a dry

basis.Calculate the molar flow rate of each species in the feed.

Calculate the total mass flow rate into the furnace:

Check basis for composition of exhaust gas.

Try working the problem using molecular balances.

Draw and label a flow diagram and use appropriate balances to calculate the rate of change of the extents of reactions $(1)$ and $(2)$

above. Take the stoichiometric coefficients in each reaction to have units of kmoles.

Determine the mass flow rate of water in the exhaust gas and the composition of the remainder in wt$\%$ on a dry basis.

Mass flow rate of water:

Weight Percent on a Dry Basis