Solution:
A powder is to be completely dissolved in an aqueous solution in a large, well–mixed tank. An acid must be added to the solution to make the spherical particle soluble. The particles are sufficiently small (negligible shear stress) that they are unaffected by fluid velocity effects in the tank. For the case of excess acid, please derive an equation for the diameter of the particle as a function of time when mass transfer limits the dissolution : $- W_A = k_c C_{A0}$
