The elementary irreversible gas phase reaction

$2AB$

is carried out in a constant volume batch reactor where $75\%$ conversion is achieved in $1$ hour. Pure A was charged to the reactor at an initial concentration of $0\mathrm{.}2mo\frac{l}{d}{m}^3.$ If the same reaction is carried out in a CSTR$,$ what volume would be necessary to achieve $75\%$ conversion for a feed molar flow rate of $750mo\frac{l}{h}$ and an entering concentration of A of $0\mathrm{.}2mo\frac{l}{d}{m}^3.$

$(25$ Marks$)$