posted by Anonymous .
Oxygen diffuses from the surface of insects to the interior through tiny tubes called tracheae. An average trachea is about 2mm long and has cross-sectional area of 2×10−9m^2. Assuming the concentration of oxygen inside is half what it is outside in the atmosphere. Find the concentration of oxygen in the air (assume 21% is oxygen) at 20∘C.Calculate the diffusion rate JJ. Assume the diffusion constant is 1×10−5m^2.Estimate the average time for a molecule to diffuse in.