4.4 - Group 2, Alkaline Earth Metals

• Where are they found

  in rocks as minerals
• trends in atomic radius


  increases down the group because all electrons feel the same net pull to nucleus but number of shells increases so atoms get bigger down the groupincreases down the group because all electrons feel the same net pull to nucleus but number of shells increases so atoms get bigger down the group
• trend in first ionisation energies

  decreases down the group because number of shells increases & effective nuclear charge remains the same so more shielding so electrons are further away from nucleus so attraction is weaker so outer election is easier to remove
• trend in reactivity


  increases down the group because it's easier to remove outer 2 elections due to decrease in first & second ionisation energies
• trend in electronegativity


  decreases down the group because atom gets bigger so bonding pair gets further away from nucleus so is less strongly attracted to it

  as you go down the group bonding becomes more ionic
• boiling point


  no obvious pattern
• melting point


  decreases down the group
• Oxidation state


  +2
• electronic configuration ands in

  S2
• compared to group 1 metals group 2 metals are

  harder

  denser

  have higher melting temperatures
• what covers the surface of group 2 metals in air

  a layer Of oxide
• properties of beryllium


  strong

  high melting point

  less dense than transition metals
• use of beryllium


  make alloys with other metals
• how is magnesium Manufactured

  electrolysis of molten magnesium chloride from sea water or salt deposits
• use of magnesium


  make light alloys as it has a low density

  used in car & plane manufacture
• properties of barium


  soft

  silvery white
• how is barium stored

  under oil because it's so reactive with air & moisture