11
PAPER CHROMATOGRAPHY
OBJECTIVES
- Separate mixtures of compounds, using the technique of paper chromatography
- Identify compounds contained in some common ink dyes
- Compare formulations of inks in various brands of pens
PURPOSE
In this experiment, you will use the technique of paper chromatography to separate the colored dyes in a variety
of felt tipped pens. You will then compare the chromatograms of the pens to those of know dyes to identify the
dyes used in the pens.
EXPERIMENTAL DATA
Tape or staple your dry chromatograms here.
QUESTIONS FOR ANYALYSIS
Use what you learned in this experiment to answer the following questions.
1. What happens to the ink spots as the chromatogram develops?
2. Why?
3. If one dye moves faster than another, which one dissolves more readily in the moving solvent?
4. Which one dissolves more readily in the water that is attached to the stationary paper?
5. Which ink dyes (specify original color) are probably made up of only one compound?
6. How can you tell?
7. How can you tell which ink dyes are made up of two compounds?
8. How can you tell if both brands of pens use the same combination of dyes to make a color?
9. Compare your two chromatograms by placing them side by side. By noting the color and position of each
spot, tell which pens (color and brand) contain the same
a. light blue dye
b. red dye
c. yellow dye