1. Propertise
   1. reactive
      1. less so than group 1
         1. 2 electrons
         2. activation energy higher
      2. increase down group
         1. outer electrons further from nulceus
      3. air
      4. water
   2. harder than group 1
   3. shiny when cut
      1. tarnish quickly
      2. oxide forms on surface
   4. higher melting point then group 1
   5. higher density than group1
2. reaction
   1. air / oxygen
      1. burn easily
         1. calcium
            1. brick-red
         2. strontium
            1. crimson
         3. barium
            1. apple green
         4. magnesium + oxygen ---> magnesium oxide
         5. 2Mg (s) + O2 (g) ---> 2MgO
   2. water
      1. not as rapid as group 1
      2. calcium + wate ---> calcium hydroxide + hydrogen
      3. Ca (s) + 2H2O (l) ---> Ca(OH)2 (aq) + H2 (g)
3. Compounds
   1. white crystalline
      1. magnesium oxide
         1. MgO
      2. calcium carbonate
         1. CaCO3
   2. oxides
      1. + water
         1. hydroxides
      2. Ca)
         1. large scale in cement making
   3. carbonates
      1. decompose when heated
      2. CaCO3 (s) ---> CaO (s) + CO2 (g)
   4. all nitrates
      1. bunsen flame
      2. oxide
      3. nitrogen dioxide
      4. oxygen
      5. 2Mg(NO3)2 ---> 2MgO (s) + 4NO2 (s) + O2 (g)