1. Briefly explain the concept of steady state as it applies to diffusion.
2. (a) Briefly explain the concept of a driving force.
(b) What is the driving force for steady-state known that the concentration of nitrogen in the steel at the high-pressure surface is 2 kg/m3. How far into the sheet from this high pressure side will the concentration be 0.5 kg/m3? Assume a linear concentration profile.