The following question is based on fundamentals of mass tran

The following question is based on fundamentals of mass transfer concept: our text book is Fundamentals of Momentum, Heat and Mass Transfer 6e by James. R Welty et al. Focusing on chapters: 22.1~3 & 24.1 & 24.2 (just for your reference)

Please show your work! thanks

Solution

From Ficks law of diffusion

J = - D * (Ca (r=2cm) - Ca(r=1) / (dr)

3.2 * 10^-12 = - D * (0.05/(4*pi*2^3/3) - 0.1/(4*pi*1^3/3)) * 10^-6 / 1

D = 142.9774 * 10^-6 cm^2/s