For problems $(5)$ and $(6),$ assume the following environmental dead state and use the attached table for evaluation of enthalpy, entropy, or gibbs energy at standard reference state.

$T_o=25C,P_o=1$atm,$x_{C{O}_2,o}=370ppm,x_{H_{2}O,o}=3\%,x_{O_2,o}=20\mathrm{.}3\%,x_{N_2,o}=76\mathrm{.}66\%$

$(5)20$ Points. Find the chemical exergy of $1$ kmol of methane mixed with stoichiometric air. Express the answer per unit mass of reacted methane $($e$.$g$.$ MJ$/$kg$-$methane$).$

$(6)20$ Points. Find the chemical exergy of the products of complete combustion of $1$ kmol of methane mixed with stoichiometric air. Express the answer per unit mass of reacted methane $($e$.$g$.$ MJ$/$kg$-$methane$).$