Data for permeation of a gas species through a solid are often presented in terms of a so-called permeation constant K, which is defined as the product of the solubility constant and the diffusivity: K = bDAB DAB=diffusion coefficient). It is commonly expressed as the amount of gas [cm3/s at STP (273K and 1 atm)] permeating through a 1 cm2 cross section of solid of 1 cm thickness, for a partial pressure difference of 1 atm. For hydrogen through Pyrex glass at 1000 K, K = 1.2X10^-8 cm^2/s-atm and DAB = 2X10^-8 cm^2/s. Find the solubility of hydrogen in glass, in mass fraction units (i.e., grams of H2 per gram of glass per atmosphere partial pressure). Take the density of the glass to be 2.4 g/cm3.
(Ans: 2.3X10^-5 g H2 / g glass-atm