Section 3: Metals Objectives: describe chemical and physical properties of metals identify and describe different kinds of metals, and compare the properties of the various families of metals Copper wire is very ductile Gallium has a low melting point

Physical Properties of Metals malleable –describes material that can be pounded or rolled into shape. ductile –describes material that can be pulled out into a long wire.

conductor –substance that electrons move freely, transmits heat or electricity. magnetic –metals that are attracted to magnets and can be made into magnets. -only iron, cobalt and nickel are naturally magnetic

Chemical Properties of Metals corrosion –gradual wearing away of a metal element caused by chemical reaction. Metals show wide range of chemical properties From very reactive (Groups 1 and 2) unreactive(gold and chromium) corrosive

Alloys alloy –substance made of two or more elements, at least one of which is a metal, that has the properties of metal.

Alkali Metals elements in Group 1 Only found as a compound in nature BECAUSE: –Very reactive -have 1 valence electron Easily transferred to another atom Very soft and shiny –Can be cut with plastic knife

Sodium is less dense than water so it appears to dance when in contact with the water.

Alkaline Earth Metals elements in Group 2 Less reactive than Group 1 more than most Only found as compound in nature Very Reactive BECAUSE -Has 2 valence electrons -has unstable valence shell

magnesium magnesium metal ribbon magnesium ribbon burning

Transition Metals An element in Group 3 through 12 of the periodic table. Have one or two electrons in outer energy level. Less active than Groups 1 and 2 (Don’t easily give up valence electrons.)

Lanthanide and Actinide lanthanide –A group of element in the first row of the rare earth elements in the periodic table. –Soft, malleable, shiny metals with high conductivity actinide –A group of elements in the second row of the rare earth elements in the periodic table. –All are radioactive, because are unstable –After 92 all elements are man made

Yetterbium Usually, very small amount of Yb is used; either small sample of radioactive isotope as source of x-rays Neodymium Neodymium magnets are the strongest permanent magnets known (compound ---Nd 2 Fe 14 B). Used in microphones, professional loudspeakers, in-ear headphones, guitars and computer hard drives where low mass, small volume, or strong magnetic fields are required. Neodymium is used for coloring glass to make welder's and glass-blower's goggles. FYI: FOR YOUR INFORMATION Lanthanide Element examples: