Magnesium, a shiny, silver, flexible metal, burns with a white hot flash, forming a crumbly white ash. When magnesium burns in air, it is combining with oxygen, or oxidizing. Magnesium, a typical metal, gives up valence electrons during its fiery combination with oxygen. Oxygen, a typical nonmetal gains electrons. If the magnesium combined with chlorine, the scenario would be identical. When a metal loses electrons, it is oxidized. The oxidation state of the nonmetal that gains the electrons goes down, so it is reduced. This PowerPoint presentation explains the concept of oxidation/reduction. It also shows how to determine oxidation states. This is necessary because change in oxidation state is the hallmark of oxidation/reduction. Worksheets on this topic are available free of charge on my website at www.evanschemistrycorner.com.