$3\mathrm{.}30$ An industrial chemical reaction proceeds according to:

$A+B2D$

with a rate expression:

$R_A=-0\mathrm{.}5(C_A{)}^{0\mathrm{.}75}(C_B{)}^{1\mathrm{.}4},$ Note: $R_A$ has units $of$ gmo$\frac{l}{L-\text{m}\text{i}\text{n}}$

A stream of water flowing at $20\frac{L}{m}in$ and containing $0\mathrm{.}20$gmo$\frac{l}{L}$ of $A($and no B$)$ flows into a CSTR$.$ Another stream of water flowing at $30\frac{L}{?}$ min and containing $0\mathrm{.}30$gmo$\frac{l}{L}$ of $B($and no $A)$ also flows into the same CSTR$.$ They mix instantaneously and start to react.

a$.$ Draw the labeled diagram and calculate the molar flow rates of A and $B$ entering the reactor, each in gmo$\frac{l}{m}in.$

A Process Engineering Approach to Solving Problems

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b$.$ If the steady$-$state exit concentration of A is $0\mathrm{.}040$gmo$\frac{l}{L},$ and the exit concentration of $B$ is $0\mathrm{.}14$gmo$\frac{l}{L},$ how big is the reactor $(L?$

c$.$ What is the concentration of $D$ in the exit stream $(gmo\frac{l}{L})?$