Chemistry C5

Air Composition and Percentages


  • Nitrogen
  • Oxygen
  • Argon
  • Carbon Dioxide
  • Water Vapour


  • N - 78%
  • O - 21%
  • A - 1%
  • CD - 0.04%
  • WV - varies
1 of 10

Covalent Bonding

  • Atoms can gain a full outer shell by sharing their outer electrons
  • This happens between non-metal atoms and is called a covalent bond
  • The covalent bonding arises from the electrostatic attraction between the nuclei of the atoms and the electrons shared between them
  • This is stronger than the repulsion force between the two nuclei
  • The attraction holds the covalent bond together
2 of 10

Ionic Bonds

Ionic bonding involves a metal and a non-metal. The metal atom gives electron(s) a way to become a positively charged ion. The non-metal gains electron(s) to become a negatively charged ion. The ions are then held together by the force of attraction between the oppositely charged ions.

Ionic Substances

  • opposite ions attract
  • the ions attract these opposites from all directions
  • they create an ionic lattice

Ionic and Covalent - similarities

  • bond to make fulll outer shell
  • don't conduct heat well
3 of 10

Ionic Equation example

Pb2+ (aq) + NO3- (aq) -> Pb(NO3)2 (s)

Li + (aq) + Cl- (aq) -> LiCl (s)

4 of 10

Giant Ionic Structures

  • Ionic - gain or lose electrons, non-metal and metal ions
  • Soluble
  • Conducts electricity and heat
  • High melting and boiling point
5 of 10

Earths Spheres

Spheres from inside going outwards

  1. Inner core
  2. Outer core
  3. Mantle
  4. Crust
  5. Lithosphere
  6. Hydrosphere
  7. Atmosphere
6 of 10



formed when a solid, liquid or gas dissolves in a solvent


when a solute dissolves in a solvent


when a solute does not dissolve in a solvent

7 of 10

How to know which ion it is

Calcium or Zinc

  • Calcium is insoluble in excess NaOH
  • Zinc is soluble in excess NaOH

Sulphate ion

  • React it with barium ions

Carbonate ion

  • React it with dilute acid
8 of 10

How to work out percentage mass

Mass of question / total mass x 100 = percentage mass


121 / 160 x 100 = 70%

9 of 10

Definitions and Atoms keyword


capable of being hammered or pressed into shape without breaking or cracking


capable of being drawn into thin wires or sheets without breaking

Atom keywords

  • reactive
  • unreactive
  • protons
  • neutrons
  • electrons
  • energy
10 of 10


No comments have yet been made

Similar Science resources:

See all Science resources »See all All resources »