Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200°c and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6x10-11 m2 /s, and the diffusion flux is found to be 1.2 x10-7 kg/m2 .s. also, it is known that the concentration of nitrogen in the steel at the high pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3