To calculate the rate of diffusion of oxygen through a 2 cm thick slab of air, we can use Fick's first law of diffusion:J = -D * dC/dx where J is the diffusion flux the amount of substance passing through a unit area per unit time , D is the diffusivity of the substance 0.20 cm^2/s for oxygen , and dC/dx is the concentration gradient across the slab.However, we do not have enough information to determine the concentration gradient dC/dx in this problem. If you can provide the initial and final concentrations of oxygen on either side of the slab, we can calculate the rate of diffusion.