Pseudo steady state with a heterogeneous reaction. When a coal particle (MW = 12g/mol, p = 1280 kg/m3) burns in air (21% oxygen, DO2-air = 10^- 4 m2/s), it is converted to CO2 and CO gas that diffuse from the particle surface. The process is limited by counter diffusion of O2 and described by the chemical reaction:

3C(s) + 2O2(g) 2CO(g) + CO2(g)

a) State the flux relationships in the gas phase.

b) Provide the differential equation that describes the flux of oxygen as a function of radius (NO2,r).

c) Setup the pseudo steady state relationship between total molar flux and mass loss. No need to solve