Situation: A solid cylinder of benzoic acid 1.5[cm] in diameter and 20[cm] long is immersed in water at 25[C] that flows at a velocity of 20[cm/s] normal to the cylinder. The diffusion coefficients of benzoic acid are 9.3106[cm2/s] in water and 0.233[cm2/s] in air. The solubility of benzoic acid in water is 0.00336[g/cm3] and its vapor pressure is 0.30[mmHg]. Requirements: Please, estimate: (a) The rate of dissolution of benzoic acid in water, in [mg/s]. Ans.: ?? 10n[mg/s] (b) The rate of sublimation of benzoic acid if the cylinder were exposed to flowing air, everything else being the same as in (a). Ans.: ?? 10n[mg/s] Problem 12 Requirements: Repeat the previous problem for the case of otherwise quiescent water or air, subjected to natural convection. Note that neither the textbook nor the lecture notes have correlations for this case. You may resort to heat-transfer references and use proper analogies to solve this problem. Ans.: ?? 10n[mg/s]