Steam reforming of hydrocarbons is one way to make hydrogen gas (Hz) for fuel cell applications. However, the Hz-rich product gas produced by steam reforming is contaminated with 0.8 mole% monoxide (CO), which poisons the catalyst within the fuel cell, and so must be removed in order for the fuel cell to work better. It is desired to separate CO from the H₂ gas using a microporous catalytic ceramic membrane. The average pore diameter of the porous membrane material is 12 nm, and the void fraction (c) is 0.25. The system operates at 4.0 bar total system pressure and a temperature of 350 °C.

Estimate the molar concentration of CO in the gas mixture.