HCl $($A$)$ diffuses into a stationary water film $($B$)$ layer of $283$ K and $3$ mm thick. This

The HCl concentration on both sides of the film is $12\%$ and $6\%$ by weight. The density of $12\%$ HCl is $1060\mathrm{.}7$

kg m$-3$

$,$ the density of $6\%$ HCl is $1030\mathrm{.}3$ kg m$-3$

The molar weights of HCl and water are $36\mathrm{.}47$ and $18\mathrm{.}02$ kg$,$ respectively.

kmol$-1.$ Under these conditions, the diffusion coefficient of HCl in water is $2\mathrm{.}1\backslash$times $10-9$ m$2$

s

$-$one

is the steady state flux of HCl

$($kmol m$-2$

s

$-$one

$)$ Calculate as $.$