Suppose you are attempting the separation of three compounds (A, B, and C) by column chromatography...

Suppose you are attempting the separation of three compounds (A, B, and C) by

column chromatography on silica gel. You start by running a number of TLC’s in

order to find the best solvent system for the separation. The results are

summarized in the table below.

Solvent Rf for A Rf for B Rf for C

Hexane 0.00 0.20 0.00

Toluene 0.00 0.30 0.05

Diethyl ether 0.05 0.75 0.29

Ethyl acetate 0.35 0.80 0.80

a) How polar are the three compounds: low, medium, or highly polar (please

estimate)?

b) Would the column chromatographic separation of all three compounds be

possible if either toluene or diethyl ether were to be used as the mobile phase?

Please explain.

Expert Solution

A) Compound A is the least polar, as it has the lowest retention factor even with the most polar solvents which are Diethyl ether and Ethyl Acetate. Similarly, compound B is the most polar because it has a higher retention factor with the polar solvent Diethyl ether. Hence, the increasing order of polarity is A<C<B.

B) the separation of all three compounds could be possible if we were to use Diethyl ether as the solvent because the difference in the retention factor is considerable. Whereas, for Toluene, the retention factor for compound A and C are very close (i.e. 0.00 and 0.05 respectively).

queen_honey_blossom answered 2 years ago

Column chromatography is useful in the separation of compounds. Using the theory behind the technique, explain...

Column chromatography is useful in the separation of compounds. Using the theory behind the technique, explain how it works. Why do you think fluorene and 9-fluorenone where are the components of the mixture you attempted to separate?

You are asked to run a chromatographic column for separation of a mixture of compounds: CH3CH2OCH3,...

You are asked to run a chromatographic column for separation of a mixture of compounds: CH3CH2OCH3, CH3(CH2)3OH, CH3CO2H, CH3(CH2)8CH3. Two solvents have been provided i.e. acetone and hexane. Which eluting solvent would you use first and predict the order of elution for the compounds.

explanation of column chromatography. Why do the compounds separate?

What property of compounds causes separation via gas chromatography? Will compounds of a higher or lower...

What property of compounds causes separation via gas chromatography? Will compounds of a higher or lower value of this property elute off the column first? How do you tell the number of components and how to calculate their percentage?

1 A) When making the decision to use column chromatography as a separation method you must...

1 A) When making the decision to use column chromatography as a separation method you must consider the sample size as well as well as its chromatographic behavior (ability to be separated using an appropriate stationary and mobile phase). How does increasing the diameter of your column affect the separation of compounds? How does increasing the column length affect the separation of the compounds

When compounds move through a column (in a column chromatography experiment), an ideal scenario involves the...

When compounds move through a column (in a column chromatography experiment), an ideal scenario involves the compounds separating into distinct (tight) bands, and traveling at different speeds through the column. This doesn’t always happen, though, for a variety of reasons. Is it possible for the stationary phase particles (silica or alumina particles in our case) to be too large? If so, what impact would these too-largeparticles have on the separation? Briefly explain your answer

Describe the principle of separation in a column used for size – exclusion chromatography. What is...

Describe the principle of separation in a column used for size – exclusion chromatography. What is the separation range in term of molecular weight? Give the definition of “gel filtration: and “gel permeation”.

1) Matching. Fill in the number matching column A with the column B _______ adsorption chromatography ...

1) Matching. Fill in the number matching column A with the column B _______ adsorption chromatography 1. Solute equilibrates between mobile phase and surface of stat. phase _______ Reverse phase 2. Effluent from a chromatographic column _______ ion-exchange chromatography 3. Relates resolving power of a column with parameters that cause peak broadening _______ molecular exclusion chromatography 4. The most common type of column used in partition chromatography _______ affinity chromatograhy 5. Different size solutes penetrate...

Explain the differences between gel electrophoresis and column chromatography. Address the principles behind each separation. Why...

Explain the differences between gel electrophoresis and column chromatography. Address the principles behind each separation. Why do large molecules migrate more easily in one method and with more difficulty in the other? Which method generated the most precise results?

1- Brief discussion of column chromatographic separation (solvent polarity, elution of compounds etc.) 2- Relationship between...

1- Brief discussion of column chromatographic separation (solvent polarity, elution of compounds etc.) 2- Relationship between polarity and thin layer chromatography.

Question