To calculate the rate of diffusion of oxygen gas through the platinum sheet, 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 diffusion coefficient 2.2 x 10^-5 cm/s for oxygen in platinum , and dC/dx is the concentration gradient across the platinum sheet.However, we don't have enough information to determine the concentration gradient dC/dx directly. Instead, we can use the following equation to estimate the rate of diffusion:Q = D * A * C / Lwhere Q is the rate of diffusion, A is the surface area 10 cm , C is the difference in concentration across the platinum sheet, and L is the thickness of the sheet 0.1 mm or 0.01 cm .Since we don't have the value for C, we cannot calculate the exact rate of diffusion. However, if we assume that the concentration difference is maintained constant across the platinum sheet, we can calculate the rate of diffusion as a function of C:Q C = 2.2 x 10^-5 cm/s * 10 cm * C / 0.01 cmQ C = 22 * CSo, the rate of diffusion of oxygen gas through the platinum sheet is 22 times the concentration difference across the sheet.