Gaseous hydrogen at 10 bars and 27°C is stored in a 100-mm-diameter spherical tank having a steel wall 2 mm thick. The molar concentration of hydrogen in the steel is 1.50k mol/m3 at the inner surface and negligible at the outer surface, while the diffusion coefficient of hydrogen in steel is approximately 0.3 x 10-12 m2/s. What is the initial rate of mass loss of hydrogen by diffusion through the tank wall? What is the initial rate of pressure drop within the tank?