Group 2

• Group 2 elements form plus two ions when they react
• Electron configuration of group 2 elements

  Ends in S2
• Atomic radius of group 2 elements

  • Increases as you go down the group
• As atomic radius increases down the group


  First ionization energy decreases
• Shielding effect overrides the increase in number of protons as you go down the group
• As atomic radius increases down the group


  Melting point decreases
• Reaction of group 2 elements with water

  1. Form metal hydroxide

  2. Produce hydrogen gas
• Reactivity of group 2 elements increases down the group, except for barium which is unreactive
• Solubility trends of group 2 compounds


  • Hydroxides become more soluble down the group
  • Sulfates become less soluble down the group
• Test for sulfates


  1. Add hydrochloric acid to remove carbonates

  2. Add barium chloride to form insoluble barium sulfate precipitate
• Neutralization by group 2 compounds

  Used to neutralize acidic soils and excess stomach acid
• Barium sulfate


  • Used in medicine to image the digestive tract
• Extraction of titanium


  1. Convert titanium ore to titanium chloride

  2. Heat titanium chloride with carbon and chlorine gas

  3. Fractionally distil to purify

  4. Reduce purified titanium chloride with magnesium
• Removal of sulfur dioxide emissions

  1. Spray calcium carbonate or calcium oxide solution onto sulfur dioxide gas

  2. Forms insoluble calcium sulfate
• Calcium sulfate is useful as it can be used to make plasterboard