ALKALI METALS

The alkali metals are all soft, shiny, reactive metals. Although they are soft enough to cut with a knife, exposing a bright surface, the metals react with water and air to quickly tarnish. The pure metals are stored in an inert atmosphere or under oil to prevent oxidation. All of the metals react vigorously with water, with the energy of the reaction increasing as you move down the periodic table. None of the alkali metals exists free in nature. They are found as salts. All of the metals form crystals with the body-centered cubic structure.