Elements

Classification of Elements

- metals
- non-metals

*Some elements have properties of both metals and non-metals.
  e.g. Silicon exists as solid and is shiny like a metal. However, it is also brittle like a non-metal.
  Elements like silicon, germanium, boron and arsenic are called metalloids.
     Metals

• lustrous (shiny appearance)
• solids at the conditions of room temperature and pressure
• malleable (can be hammered into different shapes without breaking)
• sonorous (make a ringing sound when struck)
• ductile (can be drawn into wires)
• high melting points and boiling points (except for sodium, potassium and mercury(
• good conductors of heat
• good conductors of electricity in all states of matter

     Non-metals

• non-lustrous (dull appearance if solid)
• either gases, volatile liquids or solids with low melting points at room conditions 
• brittle if solid (easily broken when hammered)
• low melting points and boiling points (except for carbon and silicon)
• poor conductors of heat (except carbon in the form of diamond and graphite)
• poor conductors of electricity (except carbon in the form of graphite)