METALS, NONMETALS & METALLOIDS Chapter 9 Lesson 3

What are metals?  Make up most of the periodic table.  75% of elements are metals.  They have shiny surfaces, conduct heat and electricity well and can bend without breaking.

What are metals?  Malleability- the ability to be bent, flattened, or hammered without breaking.  Ductility – the ability to be pulled into thin wires without breaking  Corrosion – metals combine with nonmetals from the environment (ex rust)

Uses of Metals  Early man used metals for tools and jewelry.  Today we use it in buildings (steel frames, wires, pipes,) the medical field (replace bones, close wounds) and for batteries.

Nonmetals  Located on the right side of the periodic table.  Poor conductors of heat and electricity  Good insulators  Dull surfaces, break or crumble when bent  Includes the noble gases (far right column of periodic table) that do NOT interact with other elements.

Metalloids  Boron, silicon, germanium, arsenic, antimony, tellurium, & polonium  Have properties of both metals and nonmetals  Look like metals, but not as shiny  Not malleable or ductile.  Semiconductors – materials with properties between conductors and insulators

Uses of nonmetals and nonmetals.  Nonmetals are excellent insulators  Can be drawn into strong fibers to strengthen materials  Can be used to make things flameproof.  Semiconductors used to make computer chips