Reversible reactions with transition metal complexes

A series of photos of glass beakers of a clear blue liquid turning to an opaque orange. Then another clear chemical is added by syringe and the liquid turns back to clear blue.

Source: © Declan Fleming

Use this copper-based, colour-changing demonstration to introduce your 14–16 learners to reversible reactions

Introducing the concept of reversible reactions at 14–16 can be tricky as learners may have been taught that reactions are irreversible until this point. The out of the blue demonstration is a great introduction to this concept of reversible reactions, with a clear colour-changing progression of blue to gold to blue that students can easily observe. Spark scientific discussion and begin to develop your 14–16 learners’ understanding of reversible reactions and transition metal chemistry with this colourful practical. 

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