Of glue-like liquids, some of which stick more to the solid (and In the solid and more in the liquid, so it would go a bit faster.Īnother way of looking at it is to think of the liquid as a mixture Travel more slowly over the solid another one might spend less time Spend much longer in the solid phase than in the liquid, so it would Each one undergoesĪdsorption in a slightly different way and spends more or less time Mixture of quite a few different liquids. Now remember that our liquid is actually a Gluing effect called adsorption (with a d-don't confuse it withĪbsorption, with a b, where molecules of one substance are permanently Molecules between the surface of the solid and the liquid is a kind of adhesive or Pulled back again into the liquid they came from. Sucked toward the surface of the solid and stick there temporarily before being Molecules (energetic things that are constantly moving about) are The key thing to remember is that chromatography is a surface effect.Īs the liquid starts to move past the solid, some of its Moving liquid mixture spread out because they travel at different In exactly the same way, chemicals in something like a WhenĪ race starts, runners soon spread out because they have differentĪbilities. Liquid or gas, just like a load of runners all mixed up and bunched together. Starting line, you've got a mixture of chemicals in some unidentified Think of chromatography as a race and you'll find it's much simpler than it sounds. Moves, it separates out into its components on the stationary phase. Moving substance is called the mobile phase and the substance Over the surface of something else in another state of matter (a liquid or solid) that stays where it is. State of matter (something like a gas or liquid) moving The essential thing about chromatography is that we have some mixture in one Ink) dissolved in water or another solvent creeping over the surface So, with the ink and paper trick for example, we have a liquid (the Slowly past another substance, which is typically a liquid or solid. Of chemicals, which are in gas or liquid form, by letting them creep Chromatography is actually a way of separating out a mixture Misnomer because it often doesn't involve color, paper, ink, or Try experimenting for yourself!Ĭhromatography is a pretty accurate description of what happens to ink on wet paper,īecause it literally means "color writing" (from the Greek wordsĬhroma and graphe). Different inks and papers produce very different effects. Photo: What makes ink blur on wet paper? What you're seeing here is chromatography in action.