Consider the cracking of cumene $C_9{H}_{12}$ in the presence of silica$-$alumina catalyst particles at $1$

atm and $510C.$ Use the following data to calculate the effective diffusivity, and determine

the dominant mode of diffusion:

Particle diameter $=0\mathrm{.}43cm=d$

Specific surface area $=342\frac{m^2}{g}=S_g$

Particle density $=1\mathrm{.}14\frac{g}{c}{m}^3={}_s$

Porosity $=0\mathrm{.}51={}_p$

Tortuosity factor $=3={}_p$

Molecular diffusivity $=0\mathrm{.}15c\frac{m^2}{s}=D_{AB}$