2. Mass Transfer Coefficient. A spherical oxygen bubble of 4mm in diameter is suspended in stagnant water at 1atm and 25C. Neglecting the change of bubble size with time, estimate the liquid side mass transfer coefficient for O2 diffusing through water, kL= ? DO2-Water=2.2109m2/s Henry's law: PO2[atm]=4.01x104xi Hint: First show that the flux of oxygen in stagnant water can be expressed at the interface as NAr=d/2=(d/2)cDAB(xB)LM(xAixA) and since the solubility of oxygen in water is very small one can safely assume (xB)LM1