Problem $3.[0\mathrm{.}5$ pt$]$ Reactant A decomposes by three simultaneous gas$-$phase reactions to form three products, one that is desired, B$,$ and two that are undesired, C and D$.$

$AB,-r_{A1}=k_1=1,mo\frac{l}{Ls}$

$AC,-r_{A2}=k_2{C}_A=2C_A,mo\frac{l}{Ls}$

$AD,-r_{A3}=k_3{C}_A^2=C_A^2,mo\frac{l}{Ls}$

The specific reaction rates are given at $350K.$ For an entering concentration of species $A$ of $2mo\frac{l}{L},$ determine the maximum concentration of desired product $B$ obtainable in a

a$)$ Plug flow reactor

b$)$ CSTR reactor