Group 2

• Group 2 elements


  All elements in this group have an s2 electronic configuration, and so lose two electrons to become 2+ ions
• Group 2 elements


  • Act as reducing agents (electron donors)
  • Lose two electrons (oxidation number = +2)
• Group 2 elements reacting with oxygen


  Redox reaction
• Group 2 metals reacting with water

  1. Form an aqueous metal hydroxide (with the general formula X(OH)2)

  2. Produce hydrogen gas
• Solid metal dissolves and effervescence occurs due to gas production
• The pH of the solution produced would be greater than 7, as metal hydroxides are alkalis
• Atoms in group 2

  • Become more reactive down the group due to increasing atomic radius and increasing shielding, resulting in decreasing attraction between the nucleus and outer electrons, making the outer electrons easier to lose
• Reactions of group 2 compounds


  1. Oxides and hydroxides react with acids to produce a salt and water

  2. Oxides react with water to form an aqueous solution

  3. Hydroxides dissolve in water as they are alkalis, at which point they dissociate into their ions
• Hydroxides become more soluble down group 2, and the solutions become more alkaline due to higher concentrations of OH- ions
• Group 2 carbonates reacting with acids


  Neutralize acids, and react to produce a salt, water, and carbon dioxide
• Solids dissolve and effervescence occurs as gas is produced
• Thermal decomposition of group 2 carbonates

  1. Break down to form a metal oxide and carbon dioxide gas

  2. Become harder to decompose down the group (more heat required)
• Increasing ionic character down the group causes group 2 carbonates to become harder to decompose
• Uses of group 2 oxides and hydroxides

  • Calcium hydroxide used to reduce acidity of soils
  • Magnesium hydroxide used in indigestion remedies to reduce acidity levels in the stomach