"Today’s two assignments are on Chromatography and Colloids," Professor Sciuto announced to the kids. She pointed to the beaker of water with a coffee filter stuck in the top. Streaks of colored lines decorated the paper, "In this project you will separate the color black into other colors. Fold a coffee filter in half. Fold in half two more times until you have a triangular shape. Color the tip of the coffee filter with washable black marker. Get a good coat of ink on the filter. Add a small amount of water to a cup. Place the black tip of the coffee filter in the cup. Come back to the filter after an hour or two and see what happens to the ink. As the coffee filter absorbs water through capillary action, the black ink moves through the filter and is separated by the water into other colors. You should see blue, green and even red as the water separates the ink."