What is Chromatography?
Chromatography basically means “to write with colors.” It is the process of separating a mixture by passing it through a medium in which the different components of the mixture move at different rates. Russian botanist M.S. Tsewtt discovered paper chromatography in 1903. He was able to separate the pigments in plants. Paper chromatography is now used to determine the purity and make up of many compounds. In paper chromatography the mixture is dissolved in a liquid and the medium it will travel through is the filter paper. How well the pigments separate is dependent on how well they travel up the paper and how soluble they are in the solvent.
Permanent Marker Chromatography
You are probably thinking you can’t separate permanent markers. They are permanent. With the right medium you can separate the pigments in permanent markers. It is fun to see what colors the manufactures used to make the many different colors. Students will enjoy this fun chemistry experiment.
The following activity uses nail polish remover which contains acetone. It has a high odor. It should be used in a well ventilated area. In the classroom this can be done as a demonstration in the front of the room. It could also be done on a nice day outside. Students could set them up on picnic tables. Just make sure it is not windy. Good lab practices should be followed. Follow your school districts rules and keep material safety data sheets on file.
Blue had slight other shades, but was mostly blue pigments.
Since yellow is a primary color it did not separate into other pigments.
Black always has lots of color separation. Black is a combination of all the primary colors. Look closely and you will see different shades of red, blues, and yellows.
Permanent Marker in a variety of Colors
Coffee Filter Paper
Nail Polish Remover
Small Shallow tray (Pie pans or smaller work well.)
1. Draw a circle around the edge of a coffee filter with a permanent marker.
2. Fold the coffee filter in half and then in half again to form a tee pee.
3. Pour a small amount of water into the dish.
4. Place the coffee filter in the tray so it stands upright.
5. Observe as the water travels up the coffee filter, but does not separate the colors.
6. Discuss with the class why the color did not separate. (Permanent makers do not dissolve in water.)
7. Empty the tray and get a new coffee filter.
8. Draw a circle around the new coffee filter with a permanent marker.
9. Fold the coffee filter in half and then in half again to form a tee pee.
10. Put on your safety goggles.
11. Pour a small amount of nail polish remover into the dish.
12. Place the coffee filter in the tray so it stand upright.
13. Observe as the colors begin to separate and spread on the filter paper.
14. Discuss with the students what colors they see.
15. Place the coffee filter on paper towel to dry. Try another color if you want.
Check out these other chromatography lessons.