JD

Group 2

Properties of group 2

[[The reaction of group 2 elements with oxygen- REDOX[[

  • [[metals react with oxygen to form metal oxides[[
  • [[As ionisation energy decreases down group 2, the electrons are more easily removed, so the reaction with oxygen becomes increasingly vigorous down the group[[

]]The reaction of group 2 elements with water- REDOX]]

  • ]]metals react with water to form metal hydroxides and hydrogen]]
  • ]]As ionisation energy decreases down group 2, the electrons are more easily removed, so the reaction with water becomes increasingly vigorous down the group]]
  • ]]Be does not react with water or steam]]
  • ]]Mg does not react with water but does with steam]]
  • ]]Ca reacts steadily with cold water]]
  • ]]Sr and Ba react vigorously with cold water]]

{{The reaction of group 2 with dilute acids- REDOX{{

  • {{metals react with dilute acids to form metal salts and hydrogen.{{
  • {{As ionisation energy decreases down group 2, the electrons are more easily removed, so the reaction with dilute acids becomes increasingly vigorous down the group{{

Reactions of group 2

}}Reaction of group 2 oxides with water}}

  • }}PH increases with increasing concentration of OH-}}
  • }}Going down the group the solubility of metal hydroxides increases}}
  • }}therefore, the PH increases when water is added as there is more OH- ions formed}}

<<Solubility of Hydroxides<<

  • <<The solubility of the hydroxides increases down the group shown by the thinner precipitates formed.<<

[[Solubility of sulphates[[

  • [[The solubility of the sulphates decreases down the group[[

{{Group 2 carbonates{{

  • {{All group 2 carbonates thermally decompose with acids to form an oxide and the ease of these thermal decompositions decreases down the group{{

}}Uses of group 2}}

  • }}mg is used in the extraction of titanium}}
  • }}Mg(OH)2 is almost insoluble and is used to neutralise stomach acid and reduce indigestion}}
  • }}Calcium carbonate is used as an antiacid}}
  • }}Calcium hydroxide is used to neutralise acidic soil}}
  • }}calcium oxide is used for the removal of sulfur dioxide in power stations}}
  • }}barium sulfate is used for x rays}}