group 2

• All group 2 metal from ionic compounds
• group 2 metals are reducing agents
• down he group they become more reactive
• ionisation energies decrease down group 2, it is easier to remove outer electron
• when reacted with dilute HCl, bubbles of hydrogen gas are given off at a faster rate down group 2
• the group 2 metals get more reactive with oxygen down the group
• the elements become larger down the group as more shells are added
• melting point of group 2 decreases as you go down the group because the outer electron shell is further away from the nucleus
• reacting group 2 oxides with water forms an alkaline solutions
• down group 2, the solubilities of the metal hydroxides increases as does the pH of solution
• solubility of group 2 sulfates decreases down the group
• Mg reaction with Oxygen

  burns easily, bright white light
• MMg reaction with water

  vigorous reaction with steam, no reaction with water
• Mg reaction with HCl

  reacts vigorously
• Mg reaction with H2SO$

  reacts vigorously
• Ca reaction with oxygen


  red flame
• Ca reaction with water

  reacts moderately - forms a hydroxide
• Ca reaction with HCl

  reacts vigorously
• Ca reaction with H2SO4

  forms a sulfate layer ont he metal -> slows reaction
• Sr reaction with O2

  red flame
• Sr reaction with H2O

  reacts rapidly -> forms hydroxide
• Sr reaction with HCL

  reacts vigorously
• Sr reaction with H2SO4

  insoluble layer if sulfate formes, reaction ends quickly
• Ba reaction with O2


  Green flame
• Ba reaction with H20


  reacts rapidly and forms a hydroxide
• Ba reaction with HCL

  reacts vigorously
• Ba reaction with H2SO4

  insoluble sulfate layer formed on metal so reaction stopped quickly
• Be does not react with water
• Mg reacts very slowly with cold water but forms Mg(OH)2
• Mg reacts vigorously with steal to make MgO
• all group oxides are basic except for beryllium which is amphoteric
• amphoteric - acts as both an acid nd base
• all group 2 carbonates are insoluble in water
• group 2 carbonates will form soluble chloride salts when reacted with HCl
• carbonate + HCl —> chloride + H2O + CO2
• uses of calcium

  used to remove sulfur dioxide from flue gases in sulfur scrubbing

  used in agriculture (lime) to raise soil pH
• uses of barium

  used in barium meal (BaSO4) to absorb x-rays in stomach for medical imaging
• why is barium used even though it is toxic

  It is insoluble so nto absorbed by the blood, only small amount used, health benefits outweigh health risks
• uses of magnesium

  milk of magnesia (mg(OH)2) to neutralise stomach acid

  in the extraction of titanium from its ore
• reaction of titanium and magnesium

  TiCl4 + 2Mg —> Ti + 2MgCl2