CHM 3430 Unit 3 Assignment

1. (9 pts) In a reversed-phase column, a solute was found to have a retention time of 1.32 min, and an unretained species required 1.09 min when the mobile phase was 10% water and 90% ethanol. The polarity indices for water and ethanol are 10.2 and 4.4 respectively. Calculate the water-ethanol composition that should bring k to a value of 2.00. Show your work.
2. (9 pts) Example: A sample containing compound A and B was separated by thin layer chromatography, and the results are shown below

a. Calculate the retardation factor for Compound A.
b. Calculate the separation plate number for compound B.
c. Calculate the separation resolution between compound A and B.