Separate food coloring using simple chromatography (the science of separating chemicals). Only a few kitchen items are needed.
White coffee filter paper
Red and blue food coloring
Toothpicks
Water
Skewers
Glass
Cut the filter paper into large rectangles that will fit into the glass and not hit the bottom. With the toothpick take small drops of the food coloring and spot them on the paper. Repeat this 3-5 times for darker colors. In our example the first spot is red, the second is red and blue and the third is blue.
Skewer the paper near the top and suspend it in the glass. Measure where the bottom of the paper is (it does not need to be exact). Remove the paper. Add water to the glass so the water will touch the bottom of the paper but not touch the spots, when the paper is put back in the glass.
The water moves up the paper through capillary action and draws the food coloring along with it. Different molecules travel at different speeds. The blue travels the fastest in our experiment.
Do you see anything strange? The blue in our experiment actually has a little red in it. Once we observed this we went back to the box and found that the blue does have red in it.
You can see a video of the separation on Instagram. @skyekits
