In a certain apparatus used for the absorption of sulfur dioxide, so2, from air by means of water, at one point in the equipment the gas contained 10.0 % so2 by volume and was in contact with liquid containing 0.3 % so2 by weight (liquid density is 990 kg/m3). the temperature was 50 c and the total pressure 1 atm. the overall mass-transfer coefficient based on gas concentrations was kg = 7.36*10-10 kmol/( m2 s pa). of the total diffusional resistance. 47% is in the gas phase. equilibrium data at 50 c are:

kg so2/100 kg water 0.2 0.3 0.5 0.7

partial pressure so2, mm hg 29 4683 119

a) calculate the overall mass-transfer coefficient based on liquid concentrations, kl (m/s).

b) calculate the individual mass-transfer coefficients kg, ky and kc for the gas and kl and kx for the liquid.

c) determine the interfacial concentrations in both phases.