Chapter 2 : Exploring Diversity of Matter

• Ceramic

  • Made from clay
  • poor conductor of electricity
  • hard and can be moulded into shapes
  • does not corrode
  • has a high melting point
  • fragile as it breaks easily
• Metal

  • Shiny in appearance
  • Good conductor of electricity poor insulator of electricity
  • good thermal conductor or poor thermal insulator
  • can be moulded into shapes
  • can be bent without breaking
• Glass

  • transparent
  • poor conductor of electricity
  • poor thermal conductor
  • can be molded into shapes
  • has a high melting point
  • fragile as it breaks easily
• Plastic

  • Lightweight
  • does not corrode
  • can be moulded into shapes
  • has a low melting point
  • poor conductor of electricity or good insulator of electricity
  • poor thermal conductor or good thermal insulator
• Thermal conductivity

  definition : the measure of how easily heat flows through it

  Materials that allow heat to pass through them easily are called good thermal conductors

  Materials that do not allow heat to pass through them easily are called good thermal insulators or poor thermal conductors
• Melting points

  definition : The temperature at which the material changes from the solid to the liquid state
• Boiling point

  definition : the temperature at which the material changes from the liquid state to the gaseous state
• Strength

  definition : The ability to support a heavy load without changing its shape permanently
• Hardness

  definition : The resistance to wear and tear, and scratches

  A material can cut/ scratch a material that is less hard than itself but not a material that is harder

  Diamond is the hardest natural material
• Flexibility

  definiton : The ability to bend without breaking and return to its original shape and size after bending
• Density

  Definition : The amount of matter (Substance) an object has in proportion to its volume
• Volume of sphere = 3/4 pie r (cube)
• Volume of cylinder = pie x r ( square ) x h