The stationary-phase liquid in the column described in Problem 27-23 was didecylphthalate, a solvent of intermediate polarity. If a nonpolar solvent such as a silicone oil had been used instead, would the retention times for the three compounds be larger or smaller? Why?
Problem 27-23
From the data in Problem 27-22, calculate
(a) The retention factor k for each component.
(b) Selectivity factor a for each adjacent pair of compounds.
(c) The average number of theoretical plates and plate height for the column.
(d) The resolution for each adjacent pair of compounds.
Problem 27-22
A GC column was operated under the following conditions:
column: 1.10 m x 2.0 mm, packed with Chromosorb P; weight of stationary liquid added, 1,40 g; density of liquid, 1.02 g/mL pressures: inlet, 26.1 psi above room; room, 748 torr measured outlet flow rate: 25.3 mL/min temperature: room, 21.2°C; column, 102.0°C retention times: air, 18.0 s; methyl acetate, 1.98 min; methyl propionate, 4.16 min; methyl n-butyrate, 7.93 min peak widths of esters at base: 0.19, 0.39, and 0.79, respectively
Calculate
(a) The average flow rate in the column.
(b) The corrected retention volumes for air and the three esters.
(c) The specific retention volumes for the three components.
(d) The distribution constants for each of the esters.
(e) A corrected retention volume and retention time for methyl n-hexanoate.