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Thin Layer Chromatography

APCHEM-KUVXDF

Thin layer paper chromatography is performed on an unknown substance. Three solvents were tested, and the corresponding $R_f$ factors were measured:

  • 1-propanol, $R_f$ = 1.15
  • Hexane, $R_f$ = 0.32
  • Acetonitrile, $R_f$ = 1.74

Which of the following solvents would BEST separate the unknown substance with an $R_f = 1.69$ from a known substance with an $R_f = 1.53$?

A

A mixture of the 1-propanol or acetonitrile would work equally effectively at separating the unknown substance from the known substance.

B

The acetonitrile would allow for the most solute-solvent interaction with the unknown without any interference from the known substance.

C

The 1-propanol would allow the unknown to completely separate from the known substance.

D

The hexane would allow the unknown to completely separate from the known substance.