Redox reactions and reactivity of Group 2 metals
(a) the outer shell s2 electron configuration and the loss of these electrons in redox reactions to form 2+ ions
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(b) the relative reactivities of the Group 2 elements Mg → Ba shown by their redox reactions with:
(i) oxygen
(ii) water
(iii) dilute acids
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(c) the trend in reactivity in terms of the first and second ionisation energies of Group 2 elements down the group (see also 3.1.1 c)
Reactions of Group 2 compounds
(d) the action of water on Group 2 oxides and the approximate pH of any resulting solutions, including the trend of increasing alkalinity
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(e) uses of some Group 2 compounds as bases, including equations, for example (but not limited to):
(i) Ca(OH)2 in agriculture to neutralise acid soils
(ii) Mg(OH)2 and CaCO3 as ‘antacids’ in treating indigestion.
