17. A certain material "X" has an ether/water partition coefficient, KD = 3.3. If 55 mL of 12 ppt aqueous solution is extracted with 6.0 mL of ether, how much X is drawn into the ether layer?
18. The amount of mercury in a freshwater stream is determined by flowing 500 m3 of water through a charcoal filter canister. The charcoal is later extracted with aqueous HNO3 for a total extract volume of 500.00 mL. Assuming the combined capture and extraction efficiency to be 73%, what is the (w/v) concentration of mercury in the stream if the extract measures 50 ppm?
(17) Partition coefficient(K) = conc.of X in ether/conc. of X in water
Conc. of X in water = (12/1000) x (1000/55) mol/l
= 12/55 mol/l = 0.2182 mol/l
3.3 = conc.of X in ether/conc. of X in water
3.3 x conc. of X in water = conc.of X ...
Two questions on aqueous solutions and mercury in freshwater.