3.2.2 Group 2

• Magnesium + cold water

  Mg(s) + 2H20(l) -> Mg(OH)2(s) + H2(g)
• Magnesium + steam

  Mg(s) + H2O(g) -> MgO(s) + H2(g)
• Half equation for oxidation of group 2 metal (X)

  X -> X2+ + 2e-
• The solubility of group 2 hydroxides increases down the group
• The solubility of group 2 sulfates decreases down the group
• Use for Mg(OH)2

  Indigestion remedies
• Use for BaSO4

  Barium meal in X-rays
• Barium is toxic - why can it be used as a barium meal?

  BaSO4 is insoluble so is not absorbed into the body
• Use for Ca(OH)2

  Neutralising acidic soils
• Equation for use of Magnesium to extract titanium

  TiCl4 + 2Mg -> Ti + 2MgCl2