Group 1 / Alkali metals

• Why are alkali metals placed in Group 1?

  • 1 electron in the outermost shell
  • share similar chemical properties
• Why are alkali metals stored in oil?

  • stored in oil
  • very reactive with oxygen in air
• Why are Group 1 elements classified as alkali metals?

  • produce hydroxide (OH-) ions
  • when dissolved in water
  • produce alkaline solutions
• First three alkali metals of Group 1..

  • Less dense than water
  • Float on water
• Reactivity in Group 1

  • increases down the group
• Physical properties of Alkali metals

  1. Low melting points
  2. Soft when cut
  3. Lustrous
• Chemical properties of Alkali metals

  1. Highly reactive
  2. Forms white / colourless compounds
  3. Forms 1+ ions
• Describe trend of melting and boiling points

  1. Decrease
  2. Strength of metallic bonds decrease
• What elements do alkali metals react highly with?

  1. oxygen
  2. water
  3. chlorine
• What do you expect to see when alkali metals react with water?

  1. Effervescence
  2. Bubbles
  3. Fizzing
  4. Melting into a ball
  5. Move on the surface of water
• What do you expect to see of first three alkali metals reacting with water?

  1. floating on water
• What does potassium burn with when react with water?

  1. lilac flame
• How can you identify the increase in reactivity with water?

  • increase in rate of bubble production
  • flame to an explosion
• What do alkalis form when they react with water?

  • alkali hydroxide
  • alkaline solution
• Describe the trend of reactivity in Group 1

  1. Reactivity increases down the group.
  2. The electron in the outermost shell is further from the nucleus.
  3. Weaker attraction between electron in outermost shell and nucleus
  4. Therefore electron in outer shell electron can be more easily lost
• Physical properties : Transition metals v Alkali metals

  1. Transition metals = Higher melting points
  2. Transition metals = Harder
  3. Transition metals = Stronger
• Chemical properties : Transition metals v Alkali metals

  1. Transitions metals = Less reactive
  2. Transition metals = Ions with different charges
  3. Transition metals = form coloured compounds
  4. Transition metals = Used as catalysts
• As you go down Group 1, reactions with water.. 


  • more vigorous
• Describe what you would see when potassium reacts with water

  1. Reacts more vigorously
  2. Bubbles faster
• What gas is produced in reaction with water?

  1. Hydrogen
  2. Fizzing
  3. Hear a squeaky pop when burning splint is put in it
• Evidence that sodium has a low melting point when reacting with water :

  1. melts quickly (to give a silvery ball)
• When alkali metals react with chlorine..

  • alkali chloride
  • a white precipitate / solid is formed
  • a salt
• Describe what you would expect to see when sodium reacts with chlorine

  1. Flame
  2. White precipitate