Group 1 metals - alkali metals

• Group 1 elements


  Alkali metals
• Alkali metals


  • Relatively soft
  • Low densities
  • Low melting points
  • Much more reactive than other metals
  • React vigorously with water, oxygen, and group 7 elements
• As you go down the group

  • Elements become even more reactive
  • Melting points and boiling points decrease
• Common table salt (sodium) doesn't suddenly catch fire when sprinkled on potatoes, unlike cesium
• Reactivity


  How easily atoms can lose or gain electrons and react with other atoms
• Alkali metals almost always form ionic compounds with non-metals
• Ionic compounds


  Where a metal atom donates an electron to a non-metal, forming oppositely charged ions that are attracted by electrostatic forces
• Ionic compounds are generally white solids that tend to dissolve in water to form colorless solutions
• Reaction of alkali metals with water

  1. Produces metal hydroxide and hydrogen gas

  2. Becomes more vigorous going down the group, with hydrogen gas igniting
• Reaction of alkali metals with chlorine

  1. Forms white metal chloride salts

  2. Becomes more vigorous going down the group
• Reaction of alkali metals with oxygen


  1. Forms metal oxides

  2. Type of oxide depends on the particular metal
• Reaction with water group 1

  • reacts vigoursly
  • prodiced metals hydroxide and hydrogen
• group 1 reaction with chlorine gas

  • produces white metal chlorine gas
• Reaction with oxygen

  • produces metal oxide
• Why does group 1 get more reactive as they go further down the group

  increased distance from nucleis weakens attraction