• Magnetic attraction is used to separating magnetic material from a mixture of other substances.
• When a magnet is stirred through the mixture, it pulls out the magnetic material from the mixture.
• A cow magnet, for example, is given to a cow to swallow. It stays in the first stomach of the cow, keeping magnetic materials like wire and other harmful materials that cows swallow from going into the rest of their digestive system.
• Evaporation is used to separate a solid that has dissolved in a liquid solution.
• The solution is heated or left uncovered until all the liquid turns to a gas (evaporates) leaving the solid behind.
• Salt in salt water or ocean water, for example, is separated by heating the solution until all the water evaporates leaving the solid salt in the container.
• Chromatography is used to separate and analyze the solutes in a solution.
• The substances in the solution that dissolve most easily travel the furthest; and substances that do not dissolve easily do not travel very far.
• The bands of color that are formed allow scientists to identify the substances in the solution by comparing them to the location of known substances forming bands of color on different filter papers.
• Floatation is used to separate solids that float from the remaining liquid in a mixture.
• The solids are stirred and when they float to the top, they are skimmed off the surface of the liquid and put into a different container.