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How does Black Magic work? coffee filter, the water in the ink carries the pigment onto the paper. When the ink dries, the pigment remains on the paper. When you dip the paper in water, the dried pigments dissolve. As the water travels up the paper, it carries the pigments along with it. Different- colored pigments are carried along at different rates; some travel farther and faster than others. How fast each pigment travels depends on the size of the pigment molecule and on how strongly the pigment is attracted to the paper. Since the water carries the different pigments at different rates, the black ink separates to reveal the colors that were mixed to make it. In this experiment, you're using a technique called chromatography. The name comes from the Greek words chroma and graph for "color writing." The technique was developed in 1910 by Russian botanist Mikhail Tsvet. He used it for separating the pigments that made up plant dyes. Your experiment flows through a stationary substance (like your coffee filter). Since different ingredients in a mixture are carried along at different rates, they end up in different places. By examining where all the ingredients ended up, scientists can figure out what was combined to make the mixture. Chromatography is one of the most valuable techniques biochemists have for separating mixtures. It can be used to determine the ingredients that make up a particular flavor or scent, to analyze the components of pollutants, to find traces of drugs in urine, and to separate blood proteins in various species of animals (a technique that's used to determine evolutionary relationships). À̶§ Ä¿ÇÇ ÇÊÅÍ´Â ¹°°ú »ö¼Ò¸¦ ºÐ¸®ÇØ ÁÖ´Â ¿ªÇÒÀ» ÇØ ÁÖ°í ÀÖ½À´Ï´Ù .
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