I. You ran two chromatography tests, using the same dye
a. In the first experiment you used a strip of paper ten cm long, and the second 20 cm. Will the Rf value be the same or not?
b. In the first experiment you used water as a solvent, and the second ethyl alcohol as a solvent, will they be the same or different?
II. You ran two chromatography tests, with different dye
a. with the same size strip of paper, and solvent. Same or different?
I would appreciate help, and I would appreciate thorough answers more. Thank you very much.
2007-09-07 17:19:17 · 2 answers · asked by vince_oy 3 in Science & Mathematics ➔ Chemistry
1a. If your using the same dye in the same medium (solvent), then yes, the Rf values will be the same, regardless of its' length.
b. They will be different. Depending on the substance being ran through the chromatography column (depending on its polarity), the Rf values will vary greatly.
2a. They can be similiar, or quite different. It all depends on the polarity of each dye.
2007-09-07 17:32:37 · answer #1 · answered by Phillip R 4 · 0⤊ 0⤋
All other things equal, the length of paper will not effect Rf. However, the length should be long enough to allow separation to occur.
Solvent will effect Rf.
2007-09-07 17:33:49 · answer #2 · answered by cattbarf 7 · 0⤊ 0⤋