Chemistry

• Alkali Metals


  • Have to be stored in oil, very reactive
  • All have one electron in their outer shell
  • Low density
  • Soft, can be cut with a knife
  • Melting and boiling points are low, decrease as they go down the groups
  • Atomic mass increases as you go down the group
• Reactivity of Alkali Metals


  Reactivity increases down the group, because group 1 metals react by losing the single electron in the outer shell. Because of the increasing distance of the shells, the attraction between nucleus and shells decreased, making it easier to lose 1 electron.
• Reaction of Alkali Metals with non-metals


  Alkali metals reacts with non metals to form ionic compounds, these are usually white solids that dissolve in water to form colourless solutions.
• The Halogens


  • Group 7
• Halogens


  • All non-metals that have coloured vapours
  • Melting and boiling points increase down the group
  • Relative atomic mass increases as you go down the group
• Reactivity of Halogens

  Reactivity decreased as you go down the group, because all have 7 electrons in the outer shell and react by gaining an electron. The increasing distance means that the outer electron shell is less likely to gain an electron, less attraction from the nucleus pulling electrons into the atom.
• The Noble Gases


  • Group 0
• Noble Gases


  • Full outer shells
  • At room temp are all colourless gases not bonded to anything
  • Boiling points increase as you move down the group
  • Atomic mass increases as you go down the group
  • Unreactive, inert as they have 8 electrons in outer shell
• Transition Metals


  • Typical metal
  • Good conductors of heat, electricity
  • Dense, strong, shiny
  • Much less reactive that group 1 metals
  • Higher melting points than group 1 metals
• Reactivity of Transition Metals


  When reacting transition metals usually form coloured compounds.
• Rate of Reaction


  How fast the reactants are changed into products. Reactions can go at all sorts of different rates. Eg. Iron rusting = slow; explosion = fast