11. For the chromatograms below (A and B), the sample solvent is water for all three. All three
retention mechanisms are different. Propose a particle size and stationary phase, column
dimensions, flow rate, mobile phase (isocratic only), and detector. Justify the analyte
retention order based on structure.
A)
B)
mAU
40
NO
NO3
H?
AU
6
3
5
2
2
5
6
0
2
4
6
8
10
Minutes
Peaks:
1. Uracil
7.5 µg/mL
2. Pyridine
50
3. Phenol
50
4-chloronitrobenzene
4. N,N-Dimethylaniline 50
5. Toluene
60
6. p-Butylbenzoic acid 50
35
Phenol
30
25
20
Naphthalene
15
Uracil
10
5
0
2
4
6
8
10
min
C) Assign each chromatogram the appropriate column and explain why the retention order
changed (see Polar C18 Column reference in HPLC module)