Separation Technique of Paper Chromatography PDF

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SeparationTechnique : Paper ChromatographyObjectives: [3 points] To use Paper Chromatography to identify the unknown components. To know what kind of color present in the spots. To identify the retention factors of the following spots. DATA:B. Paper chromatography of amino acids.The following data a...

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Separation Technique: Paper Chromatography

Organic Chem Laboratory Manual

Separation Technique : Paper Chromatography Objectives: [3 points] •

To use Paper Chromatography to identify the unknown components.

•

To know what kind of color present in the spots.

•

To identify the retention factors of the following spots.

DA DAT TA: B.

Pa Paper per chromatogr chromatography aphy of amino acids. The following data are the results of the experiment conducted on 4 known amino acids and one unknown mixture. Calculate the Rf values of each.

1.

Rf values of test amino acids [2 point each] Distance trav traveled, eled, mm solvent tryptophan

100

Rf value N/A 0.74

74 0.66

phenylalanine

66

cystine

20

0.20

glycine

unknown

0.29 29 75

0.75

33

0.33

Separation Technique: Paper Chromatography

1.

Organic Chem Laboratory Manual

Based on your data, deduce the identity of the component/s of your unknown. [2 points]

The first unknown with 0.75 retention factor is tryptophan, and the second unknown with 0.33 retention factor is identified as glycine.

3.

At the edges of the paper which you happened to touch with sweated hands,

a)

what do you observe? [1 point] the violet spots can be seen.

b)

what can you conclude about the composition of sweat? [2 points]

The composition present are the amino acids.

QUESTIONS: Would the Rf values of the amino acids you used here be the same if you use another

1.

solvent system? (Yes or No) (1pt) No. Explain. [3 pts] If we use different or another solvent system it will actually produce a different phase in the Rf values of the amino acid.

What would happen in the following conditions? [2 points each]

2. a)

the solvent level in the developing chamber is above the applied spots? The applied spots will dissolve in the solvent.

b)

the solvent was allowed to “overrun” the paper? It won’t be allowed, because the experiment is already null because the paper is overrun and cannot be longer used to calculate the Rf.

Separation Technique: Paper Chromatography

Organic Chem Laboratory Manual

Page the spots applied were too big?

c)

It developed an overlapping and tailing of the spots.

Give the structural formula of the 4 amino acids. [4 points]

3.

a)

tryptophan

b)

phenylalanine

c)

cystine

d)

glycine

Separation Technique: Pape

4.

Organic Chem Laboratory Manual

If you were to subject a green ink to paper chromatographic separation, what are the possible colors that will appear on the chromatogram? (2 pts) Yellow and Blue

5.

What is the difference between an ascending and descending paper chromatography? (4 pts)

The Ascending Paper Chromatography is an upward direction movement of the solvent, while the Descending Paper Chromatography involves downward direction movement of the solvent.

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