Question: Carbon dioxide is diffusing through nitrogen in one direction at atmospheric pressure and 0C. The mole fraction of CO 2 at point A is 0.2;

Carbon dioxide is diffusing through nitrogen in one direction at atmospheric pressure and 0°C. The mole fraction of CO2 at point A is 0.2; at point B. 3 m away, in the direction of diffusion, it is 0.02. Diffusivity Du is 0.144 cm2/s. The gas phase as a whole is stationary; that is, nitrogen is diffusing at the same rate as the carbon dioxide, but in the opposite direction. 

(a) What is the molal flux of CO2, in kilogram moles per square meter per hour?

(b) What is the net mass flux, in kilograms per square meter per hour?

(c) At what speed, in meters per second, would an observer have to move from one point to the other so that the net mass flux, relative to him or her, would be zero?

(d) At what speed would the observer have to move so that, relative to him or her, the nitrogen is stationary?

(e) What would be the molal flux of carbon dioxide relative to the observer under condition (d)?

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To solve this problem we will use the following equations Ficks first law of diffusion J D dCdx Molal flux J N A Mass flux J m A Where J is the flux i... View full answer

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