3. You detected O2 storage tank leaked a gas at a constant rate through a 1.6mm-thick stagnant layer of air. Conditions are such that at one boundary of the stagnant layer, the gas contains 65%O2 by volume, whereas its concentration at the other boundary can be considered negligible. The total pressure and the temperature are 1 atm and 25C, respectively. Determine the rate of diffusion of O2 through the layer of air. (20p) 3. You detected O2 storage tank leaked a gas at a constant rate through a 1.6mm-thick stagnant layer of air. Conditions are such that at one boundary of the stagnant layer, the gas contains 65%O2 by volume, whereas its concentration at the other boundary can be considered negligible. The total pressure and the temperature are 1 atm and 25C, respectively. Determine the rate of diffusion of O2 through the layer of air. (20p)