A Stefan-diffusion tube, where diethyl ether (DEE, CAS No. 60297) diffuses inair at 27.85 [C] and 1[bar] where, at a given time, the molar evaporation flux si 1.674 [mmol/m2.s]. The Antoine constants for DEE (vapor pressure in [kPa]; temperature in [C], and natural logarithm) are: A = 14.0735; B = 2511.29; C = 231.2).

Experimental data: diffusion coefficient of DEE in air have been correlated according to

D= k(T)^1.8

where the empirical constant k si equal to 3.1710-10 [m2/-(K)1.8].

Additional properties of DEE are: molar mass: 0.07412 [kg/mol]; liquid density: 713.4 [kg/m3]. The molar mass of air is 0.029 [kg/mol].

Please estimate (at the conditions of the interface (on the gas side) when appropriate):

1- DEE linear velocity: (m/s)

2- Mixture average velocity as molar average and mass average:

3- DEE mass fluxes with respect to mass average velocity and with respect to a fixed reference frame:

4-DEE molar fluxes with respect to mole average velocity and

with respect to a fixed reference frame: