Lithium, sodium and potassium with water

Lithium
1. The reaction generates heat too slowly and lithium's melting point is too high for it to melt
2. Lithium's density is only about half that of water so it floats on the surface
  1. It gently fizzes and gives off hydrogen
    1. It gradually reacts and disappears
      1. It forms a colourless solution of lithium hydroxide.
Sodium
1. Sodium floats on the surface of the water
  1. Because it has a low melting point it melts
    1. It forms a small silvery ball that dashes around the surface.
      1. A white trail of sodium hydroxide is seen in the water under the sodium
        This soon dissolves to give a colourless solution of sodium hydroxide.
Pottasium
1. Potassium behaves rather like sodium except that the reaction is faster
2. Enough heat is given off to set light to the hydrogen.
  1. The normal hydrogen flame is contaminated by potassium compounds...
    1. ...and so is coloured lilac (a faintly bluish pink).

Resource summary

	Created by Emma Boxley over 11 years ago