Group 1

• • very reactive metals
• • stored under oil because they react with oxygen in air and water
• • soft metals
• • have low melting/boiling points
• • has 1 electron on the outer shell
• • they react with non-metals by losing their single outer electrons
• • reactivity of alkali metals increase down the group
• as you go down the group:

  • atomic radius increases
  • nuclear attraction decreases
  • easier to lose the outer electron
  • shielding effect from the inner shell electrons increase
• • alkali metals + water -> metal hydroxide + hydrogen
  • fizzing occurs as hydrogen gas is produced
• e.g 2Na(s) + 2H20(l) -> 2NaOH(aq) + H2(g)

  • Na floats as it's less dense than water
  • Na melts as its melting point is low + lots of heat is produced
• Li reacts slower than Na:

  • doesn't melt
  • fizzes slower on surface
  • moves slower
• K's reaction is faster than Na:

  • burns with lilac flame
  • fizzes faster
  • moves faster
  • melts
• • alkali metals burn in air, forming white metal oxides
  • 4Na(s) + 02(g) -> 2Na20(s)
• • all group 1 metals react with halogens to form ionic salts
  • 2Na(s) + Cl2 -> 2NaCl(s)