$(30)$ Arrange the equation to calculate the molar ratio air$/$CH $/H_2(4)$ in order to obtain

adiabatic flame temperature of $2000K$ when methane, at $298K,$ is combusted with air.

Assume that $C{O}_2(2)$ and $H_{-}(2)O$ are the product of combustion, During process, pressure is

constant, beside adiabatic process. Use first law analysis for calculation, Use the data given in

the appendix. Leave the calculation in integral form. Consider excess air if exist!

$C{H}_4(g)+2O_2(g)=>C{O}_2(g)+2H_{2}O(g)at298K$