Bonding, structure and prop of matter 2

• What is the structure of solids?

  • packed tightly
  • vibrate about fixed positions
  • strong forces of attraction
  • fixed shape
• What is the structure of liquids?

  • randomly arranged
  • free to move around
  • no orderly arrangement
• What is the structure of gases?

  • move around completely freely
  • mostly empty space
  • ver weak
• what is melting? Phase transition from solid to liquid.
• What is boiling?


  when a liquid boil.
• What is condensation?


  The process of a gas turning into a liquid.
• What is freezing?


  The process of a substance changing from a liquid to a solid state due to a decrease in temperature.
• How are positive ions formed?

  By losing electrons.
• How are negative ions formed?

  Electron gain
• Are positive ions metals or non metals?

  metals
• Are negative ions metals or non metals?


  non metals
• How are ionic bonds formed?


  when metal elements react with non metal elements.
• What are covalent bonds?


  Are strong bonds that form between two or more atoms that are both non metal elements
• Properties of simple covalent molecules:

  • bonds between atoms are strong and difficult t break but forces between molecules are usually very weak
• What are giant structures in chemistry?

  Macromolecules
• What are polymers? 


  type of covalent molecules, long chains of carbon atoms
• What is metallic bonding?

  they form Lattice (grid) of ions surrounded by a sea of delocalised electrons.
• Ionic bonds have...

  • high melting point
  • boiling point due to string ionic bonds
• examples of giant covalent bonds

  • diamond
  • silicon dioxide
• Diamond:

  • hard due to strong bonds
• Graphite:

  • delocalised electrons form weak bonds between layers
  • conduct electricity as electrons can move freely
• What are alloys?


  Are mixtures of metals with different size atoms which disrupt the lattice, so layers can't slide-strong
• What is graphene?


  A single layer of carbon atoms arranged in a hexagonal lattice.
• what is fullerene's/nanotubes used for?

  • electronics
  • medical purposes
• Size of nanoparticles?


  1-100nm
• Size of fine particles?

  100-2500nm
• Size of coarse particles (dust)?

  2500nm
• Why are fullerenes useful?

  due to there high surface to volume ratio

  Double the length=half the ratio