VI. Four compounds were analyzed on tlc plate after spotting them and developing them with 75% Ethyl acetate in hexane: Distance travelled by the solvent is: 8.0 cm Distance travelled by Compound A is: 6.5 cm Distance travelled by compound B is: 4.85 cm Distance travelled by compound C is: 2.85 cm Distance travelled by Compound D is 1.022 cm Calculate the Rf values of A, B, C and D Rf value of A: Rf value of B: Rf value of C: Rf value of D:

VI. Four compounds were analyzed on tlc plate after spotting them and developing them with 75% Ethyl acetate in hexane: Distance travelled by the solvent is: 8.0 cm Distance travelled by Compound A is: 6.5 cm Distance travelled by compound B is: 4.85 cm Distance travelled by compound C is: 2.85 cm Distance travelled by Compound D is 1.022 cm Calculate the Rf values of A, B, C and D Rf value of A: Rf value of B: Rf value of C: Rf value of D:

EBK A SMALL SCALE APPROACH TO ORGANIC L

4th Edition

ISBN:9781305446021

Author:Lampman

Publisher:Lampman

Chapter89: Thin-layer Chromatography

Section: Chapter Questions

Problem 5P

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Similar questions

Which combination cannot be used as mobile phase in RPLC? A. Acetonitrile-cyclopentane B. Water-acetonitrile C. Acetonitrile-THF D. Water-THF
if you wanted to makes the spots travel up the TLC plate further, what solvent ration would you choose and why? 1:2 Ethyl acetate/Hexane, 2:3 Ethyl acetate/ Hexane, or 1:1 Ethyl acetate/Hexane
In what order would the following compounds be eluted on a silica gel TLC plate if they are spotted on the same plate and developed in a solvent mixture of 10:1 hexanes:ethyl acetate A. 1 has the highest Rf value, then 2 then 4 then 3 b. 4 has the highest Rf value, then 1 then 3 then 2 c. 3 has the highest Rf value, then 2 then 1 then 4 d. 2 has the highest Rf value, then 3 then 1 then 4
Regarding TLC: a) Compounds A and B are analyzed side-by-side by TLC on silica gel. The developed chromatogram is shown. Which compound is more polar? b) Three unknown mixtures (X, Y, and Z) are analyzed by TLC. The developed plate is shown. What can be concluded about unknown Y? A. Unknown Y contains exactly two different compounds. B. Unknown Y contains at least two different compounds. C. Nothing can be concluded.
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Both melting points and TLC rely on differences in non covalent forces. Explain the role of these non-covalent interactions in the final answer obtained (melting point and Rf value).
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When you run a TLC plate with methyl orange and biphenyl, you observe very large, broad, streaky spots on the plate under the UV light. What is the most likely explanation? a. The elution solvent was too polar. b. Too much sample was spotted onto the TLC plate. c. Too little sample was spotted onto the TLC plate. d. The elution solvent was not polar enough. e. The Rf of the components was too high.
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This is an illustration of TLC plates. The compounds used were syn-azobenzene (A) and anti-azobenzene (B). The difference between the two plates are that the first was placed in 15% methylene chloride in pet. ether and the second was placed in 30% methylene chloride in pet. ether. I calculated Rf values to be 0.47 mm for syn-azobenzene and 0.44 mm for anti-azobenzene in 15% while syn-azobenze had a Rf of 0.28 mm and 0.16 mm. Which solvent is best at separating and how does Rf help identify which isomer is which? I read that the anti is supposed to have a higher Rf but that is not the case here so I want to know if the syn is supposed to have the higher Rf and the anti is supposed to have the lower one.
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