From distribution studies, species M and N are known to have water/hexane distribution constants of 5.99 and 6.16 (K = [X]_H2O/[X]_hex), where X = M or N. The two species are to be separated by elution with hexane in a column packed with silica gel containing adsorbed water. The ratio V_S/V_M for the packing is 0.425.
(a) Calculate the retention factor for each solute.
(b) Calculate the selectivity factor.
(c) How many plates are needed to provide a resolution of 1.5?
(d) How long a column is needed if the plate height of the packing is 1.5 x 10^-3 cm?
(e) If the flow rate is 6.75 cm/min, how long will it take to elute the two species?