Question $1$:

At a total pressure of $101\mathrm{.}3$kPa and $293K,C{O}_2(A)$ is diffusing at steady state through an inert nondiffusing mixture of nitrogen $(B)$ and oxygen $(C).$ The mole fractions at $z_1=0$ are $x_{A1}=0\mathrm{.}8,x_{B1}=0\mathrm{.}15,$ and $x_{C1}=0\mathrm{.}05$; and at $z_2=4\mathrm{.}0mm,x_{A2}=0\mathrm{.}2,x_{B2}=0\mathrm{.}6,$ and $x_{C2}=0\mathrm{.}2.$ See Table $18\mathrm{.}2-1$ for molecular diffusion coefficients. Calculate the flux of $C{O}_2.$