In an absorber operating at atmospheric pressure and $300$K$,15\%$ CO$2-$air mixture is scrubbed with

dilute NaOH$-$water solution and the concentration of CO$2$ in the air is reduced to $0\mathrm{.}3\%.$ The mass transfer is

controlled by the thin laminar film on the gas side of the gas$-$liquid interface. At some intermediate point, where

the CO$2$ concentration in the gas phase has been reduced to $7\%,$ the partial pressure of CO$2$ in equilibrium with the

average solution is $0\mathrm{.}70$ kPa and the transfer rate has been determined to be $1\mathrm{.}1$ mol$/$m$2/$sec$.$ Compute the

thickness of the hypothetical gas film. Diffusivity of CO$2$ in air may be taken as $0\mathrm{.}24$ cm$2/$sec