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Chromatography
Manthan Parekh and Jeny Shah*
The Community College of Baltimore County
2701 Rossville Blvd, Baltimore, MD 21237
26th September 2018
Abstract:
The purpose of this experiment was to find different the cations in the unknown substances. The process of chromatography was used by allowing the fumes of the solvent to show different colors and the distance traveled. There are 5 cations used in this experiment to determine the unknown which are (CO2+, Cu2+, Fe3+, Mn2+, Ni2+). The ions have a unique chemical property which aid in determining the unknows. To determine the unknown the Rf value and visual comparison.
Introduction:
Chromatography is the separation of elements within a compound. There are many ways to do chromatography for depending on each set mixtures. In this process the solutions of each elements are placed on one side and the unknow at the end. In the results the unknown mixture will show how each component with the mixture of which elements were added with at most 3 cations. The distance of each cations obtained, and unknowns used. The RF value is obtained through the equation given below.

Rf = (Distance traveled by component)/(distance traveled by solvent)
Experimental Section:
In the chromatography chamber jar 20 mL of solvent was added and then covered. A chromatography paper was obtained and drawn upon. On a landscape orientation a solid line was drawn above the base 1.50 cm. At the start of the line 2.50 cm was measured off and continued with every increment of 2.00 cm. Another line was made 5.00 cm above the previous line with labels of (CO2+, Cu2+, Fe3+, Mn2+, Ni2+, and 2 unknows) a spot was placed using a capillary tube on the base line. After it was completed a few minutes were given to dry the spots and placed into the chromatography chamber jar. As several minutes pass by until it achieves optimal height. It was then taken out of the jar and dried. The paper was then sprayed with aqueous ammonia, dimethyl glyoxime and NaOH separately with each several minutes time lapse to also each color to be seen and measured by the use of a 12 inch ruler in centimeter.

Results and Discussion:

The image above shows the experimental cations color and unknown colors. There are colors in each different cation and then used to record color and distance traveled for each component. The tables below show the values and colors for each cation and distance.
CO2+ Cu2+ Fe3+ Mn2+ Ni2+
Color of sample Red Blue Yellow White Green
Color of spots after removal from chamber Red Blue Yellow Clear Clear
Color of spots with NH4OH Clear Clear Yellow Brown Clear
Color of spots with DMG Light green Brown Yellow Brown Pink
Color of spots with NaOHYellow Dark Brown Yellow Dark Brown Pink
Distance traveled by component (cm) 2.72 3.08 4.40 3.01 1.48
Distance traveled by solvent (cm) 5.00 5.00 5.00 5.00 5.00
Rf Value 0.544 0.616 0.880 0.602 0.296
Unknow # 17 Spot 1 Spot 2 Spot 3
Color of sample Red Red Red
Color of spots after removal from chamber Clear Clear Clear
Color of spots with NH4OH Clear Clear Yellow
Color of spots with DMG Clear Light Brown Yellow
Color of spots with NaOHClear Brown Yellow
Distance traveled by component (cm) 1.02 2.99 4.34
Distance traveled by solvent (cm) 5 5 5
Rf Value 0.204 0.598 0.868
Unknow # 9 Spot 1 Spot 2 Spot 3
Color of sample Light Blue Light Blue Light Blue
Color of spots after removal from chamber Clear Clear Clear
Color of spots with NH4OH Clear Clear Clear
Color of spots with DMG Pink Clear Yellow
Color of spots with NaOHPink Brown Yellow
Distance traveled by component (cm) 0.52 3.56 4.52
Distance traveled by solvent (cm) 5 5 5
Rf Value 0.104 0.712 0.904
Conclusion:
The unknows that were obtained unknow #17 to have iron and copper, the unknown number #9 had nickel, iron and copper. Each of these cations were obtained through estimation of colors and distance traveled. In each of the cations few had larger spots due to capillary tubes droplets. Towards the end the unknows was given a clear and precise data to show each cation.
References:
Hamilton, P., CHEM 131 – General Chemistry I & laboratory; Academx Publishing Services: Baltimore, MD, 2018, p.p. 45-54

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