Question 24.3: Reevaluate the diffusion coefficient of carbon dioxide in ai...
Reevaluate the diffusion coefficient of carbon dioxide in air at 20^{\circ} \mathrm{C} and atmospheric pressure using the Fuller, Schettler, and Giddings equation and compare the new value with the one reported in example 2.
\begin{aligned} D_{A B} & =\frac{10^{-3} T^{1.75}\left(\frac{1}{M_{A}}+\frac{1}{M_{B}}\right)^{1 / 2}}{P\left[\left(\sum v\right)_{A}^{1 / 3}+\left(\sum v\right)_{B}^{1 / 3}\right]^{2}} \\ & =\frac{10^{-3}(293)^{1.75}\left(\frac{1}{44}+\frac{1}{29}\right)^{1 / 2}}{(1)\left[(26.9)^{1 / 3}+(20.1)^{1 / 3}\right]^{2}} \\ & =0.152 \mathrm{~cm}^{2} / \mathrm{s} \end{aligned}
This value compares very favorably to the value evaluated with Hirschfelder equation, 0.155 \mathrm{~cm}^{2} / \mathrm{s}, and its determination was easily accomplished.