Metals Section 20.1

Properties Metals- good conductors of heat & electricity. All but one are solid at room temperature. Lustrous- reflect light, Malleable- can be hammered or rolled into sheets, Ductile- can be drawn into wires Metals- have 1-3 valence electrons, so they lose electrons to become stable Metallic bonding- positively charged metallic ions are surrounded by a cloud of electrons. Outer electrons are not held tightly and can move among the ions- allows conduction of electricity

Metals Alkali metals- softer than other metals Most reactive metals- react violently with oxygen and water and do not occur in nature as pure elements Group 2 metals- Alkaline earth metals Transition elements- Groups 13-18, metals, often form colored compounds Gold- unreactive and soft- easily shaped Zinc- used as a coating because it combines with the air for form a protective coating of zinc oxide

Metals Lanthanides are elements after lanthanum and many are used to produce colors on our TV screens Actinides- follow actinium. All are radioactive and unstable, so they are difficult to research Ore is a metal compound (mineral) within a mixture of clay or rock. Mineral is converted to another form through heat. Metal is then refined into a pure form through chemical reactions

Metals Elements beyond Uranium are radioactive- As # of protons increases, the repulsive force within the nucleus also increases- forces the atom to break apart. (Radioactive substances are substances in which the nucleus breaks down and gives off particles and energy )