cornea
12.7 Molecular Transport Phenomena: Diffusion, Osmosis, and Related Processes 62. You can smell perfume very shortly after opening the bottle. To show that it is not reaching your nose by diffusion, calculate the average distance a perfume molecule moves in one second in air, given its diffusion constant D to be 1.0010 6 m 2 /s . What is the ratio of the average distances that oxygen will diffuse in a given time in air and water? Why is this distance less in water equivalently, why is D less in water ? 64. Oxygen reaches the veinless cornea of the eye by diffusing through its tear layer, which is 0.500-mm thick. How long does it take the average oxygen molecule to do this? 65. a Find the average time required for an oxygen molecule to diffuse through a 0.200-mm-thick tear layer on the cornea. 3 b How much time is required to diffuse 0.500 cm of oxygen to the cornea if its surface area is 1.00 cm 2 ? 66. Suppose hydrogen and oxygen are diffusing through air. A small amount of each is released simultaneously. How much time passes before the hydrogen is 1.00 s ahead of the oxygen? Such differences in arrival times are used as an analytical tool in gas chromatography.