PROBLEM

A vertical glass tube $3mm$ in diameter is filled with liquid toluene to a depth of $20mm$ from the top opened. After $275$ hrs at $39\mathrm{.}4C$ and a total pressure of $760mmHg$ the level has dropped to $80mm$ from the top. Calculate the value of diffusivity.

Data:

vapor pressure of toluene at $39\mathrm{.}4C=7\mathrm{.}64k\frac{N}{m^2},$

density of liquid toluene $=850k\frac{g}{m^3}$

Molecular weight of toluene $(C_6{H}_{6}C{H}_3)=92$

$760mmHg=101\mathrm{.}3k\frac{N}{m^2}$