How to Do a Black Ink Chromatography Science Experiment

Black ink chromatography sounds as though it would be a very scientific and complicated experiment, but it's really not. If you're a true crime follower, you probably know that chromatography is the technique forensic scientists use to separate out and analyze all the trace elements found in a person's blood. The black ink science experiment isn't nearly that sophisticated. It's merely a way to separate the different color inks that combine to make black in your run-of-the-mill markers. Still, it's fun and a great way to show kids how different pigments travel at different rates. Read on to learn how to do a black ink chromatography science experiment.

Instructions

Perform Marker Magic

1

Choose a place to conduct your experiment and cover the table with old newspaper or a plastic tablecloth. Once the table has been prepared, place a white coffee-filter flat on the table.

2

Draw a dot in the middle of the coffee filter with a water-soluble black marker. Most markers will work well for this experiment, but be sure the marker is not permanent, since permanent ink is constructed differently than the water-soluble variety.

3

Fill a glass or small bowl with about an inch of water. Using an eyedropper or small pipette, drip water, one drop at a time, onto the black circle. Continue dropping water until the circle begins to expand outward on the coffee filter.

4

Watch as the water performs chromatography.You'll notice that the rings are different colors. The water acts as a catalyst to separate the colored pigments that combine to make black. Each pigment travels a certain distance away from the center, depending on how large it is and how well the filter attracts it. This leaves a rainbow-colored ring.

Make a Colorful Man

5

Cut a rectangular strip from a coffee filter.

6

Use your black marker to draw a man approximately an inch from the bottom of the strip.

7

Hang the strip over the side of a clear glass, so that the drawing is inside the glass. You may want to tape the other edge to the side of the glass to hold it in place.

8

Pour approximately an inch of water in the glass, without wetting the drawing, but making sure it's just above the water line.

9

Wait as the water is wicked up through the filter paper. The man should not only appear to stretch, but as he does so, he'll dissolve into bands of color.