Properties and Uses of Metals

• Elements that display properties of both a metal and a non-metal are called metalloids or semimetals
• properties of metals

  • conducts heat and electricity because there are free electrons available to move through the structure and carry charge
  • are malleable (can be hammered and made into different shapes)
  • ductile (can be drawn into wires)
  • tend to be lustrous (shiny)
  • have high density and usually high m.p
  • form positive ions through electron loss
  • form basic oxides (a few are amphoteric oxides)
  • electron arrangement: 1-3 (more in periods 5 & 6) outer shell electrons
  • metallic bonding due to loss of outer shell electrons
  • many react with acids
• properties of non-metals

  • do not conduct heat and electricity
  • are brittle when solid and easily break up
  • tend to be dull and non-reflective
  • have low density and low melting points (many are gases at room temperature)
  • form negative ions through electron gain (except hydrogen)
  • form acidic oxides (some are neutral)
  • 4-7 electrons in the outer shell
  • covalent bonding by sharing of outer shell elecrons
  • do not react with acids
• uses of aluminum

  • airplane bodies: high strength-to-weight ratio, low density
  • overhead power cables: good conductor of electricity, low density
  • saucepans: good conductor of heat
  • food cans: non-toxic, resistant to corrosion and acidic food stuffs
  • window frames: resistant to corrosion

  uses of copper

  • electrical wires: good conductor of electricity and malleable
  • water pipes: easy to work with and bend, non-toxic and unreactive (does not react with water)