Lab 22 Experiment 1 Post-lab Questions 5d1q6c

Separation by Chromatography Table 1: Paper Chromatography Data and Observations Solvent

Distance Traveled Distance Traveled by Mobile Phase by Each Analyte (mm) (mm)

Rf Value

1: Distilled Water

45

Green: 33 Blue: 41 Red: 26

Green: 0.73 Blue: 0.91 Red: 0.58

2: 0.5% NaCl Solution

51

Green: 32 Blue: 40 Red: 23

Green: 0.63 Blue: 0.78 Red: 0.45

3: 0.2% NaCl Solution

53

Green: 36 Blue: 41 Red: 26

Green: 0.68 Blue: 0.77 Red: 0.49

32

Green: 19 Blue: 18 Red: 18

Green: 0.59 Blue: 0.56 Red: 0.56

4: 70% Isopropyl Alcohol

Additional Observations

Post-Lab Questions 1. Which solvent provided the best separation?

The solvent to provide the best separation rate is 0.2% NaCl.

2. Explain which characteristics of the solvent were used to effectively separate the analytes.

The sodium chloride had the same polarity as the stationary phase and could separate out. Polar compounds that are initially attracted to the polar stationary particles can be eluted to a lower percent solution by adding water which increase polarity of the mobile ©eScience Labs, LLC 2015

Separation by Chromatography phase.

3. Which solvent provided the second-best separation? Try to identify some similarities between the two solvents that could for the success of separation.

The second-best separation solvent provided is 0.5% NaCl. Similarities are that they are both salts, both sodium chloride, both in solution, have same polarity and ionic charges.

4. Some children have reactions to Yellow 5 or Yellow 6 dye. Yellow 5 is a pale yellow color and Yellow 6 is more orange. Use the colors seen on the chromatograms to determine which M&Ms® candies you tested contain Yellow 5.

M&Ms® candies that has a change to yellow 5 pale color is the green dye because this color has blue and yellow color in it so when is diluted in each solution the green color turns lighter.

5. We have mentioned that chromatography has many applications. Research one application of chromatography and explain how it is used and what characteristic is utilized for the separation of the analyte(s).

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Separation by Chromatography Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Chromatography technique is a valuable tool for biochemists, besides it can be applied easily during studies performed in clinical laboratories. For instance, paper chromatography is used to determine some types of sugar, and amino acids in bodily fluids which are associated with hereditary metabolic disorders.

6.

Traditionally in chromatography the eluting solvent is an organic compound, such as hexane or acetonitrile. Explain, in of green chemistry, why this experiment uses environmentally friendly compounds, such as table salt, water, and isopropyl alcohol. Research an alternative solvent that is currently being used in chromatography to reduce costly wastes and describe the benefits of that solvent, as well as any complications that may be related to the use of the alternative solvent.

Alternative solvents are considered in of toxicity, cost, safety, workability, chromatographic selectivity and elution strength. The less toxic solvents are ethanol, acetone and ethyl acetate as possible greener replacements for methanol, acetonitrile and tetrahydrofuran.

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