The secondary bonding of gas molecules to a solid surface is a common mechanism for measuring the surface area of porous materials, by lowering the temperature of a solid well below room temperature, a measured volume of gas will condense to form a monolayer coating of molecules on the porous surfacce. For a 100g sample of fused copper catalyst, a volume of 9*10^3 mm^3 of nitrogen (0C, 1atm) is required to form a monolayer upon condensation. calculate the surface area of the catalyst in unit of m^2/kg. take area covered by nitrogen molecule as .162nm^2.