The Colour of a Metal Compound is a result of a partially filled d-orbital    

Copper Sulphate and Sodium Thiosulphate

This practical demonstrates the addition of sodium thiosulphate to some Copper sulphate solution. The Thiosulphate acts as a reducing agent and reduces the Copper(II) ion to Copper(I) ion.

Right click and open in a new window to view of PowerPoint presentation slide which shows the colour of Copper(II) and Copper(I) ions.

Right click and open in new window to view a Word document which includes photographs at the start and end of the experiment and has questions which could be used during discussion of this experiment.

Left click to view high quality video or right click to download (3.7MB)

For more information see 'School Experiments - A collection of tried and tested experiments for use in schools - ASE Ralph F Farley'