Oxygen is diffusing in a mixture of oxygen-nitrogen at 1 std atm, 25°C. Concentration of oxygen at planes 2 mm apart are 10 and 20 volume % respectively. Nitrogen is non-diffusing.
(a) Derive the appropriate expression to calculate the flux oxygen. Define units of each term clearly.
(b) Calculate the flux of oxygen. Diffusivity of oxygen in nitrogen = 1.89 * 10^-5 m^2/sec.