Dancing flames

When teaching the reactivity series, aluminium’s protective oxide layer can make it difficult for students to see its true reactivity in the context of metals reacting with aqueous solutions.

A demonstration involving mercury(II) chloride is described in Classic chemistry demonstrations and can be found on the Practical Chemistry website. That experiment shows how removing the protective layer causes the aluminium to react with air. However, this demonstration shows its reaction in solutions that students are likely to have already met. With a little practice, it has the added wow factor of burning with an eerie green flame that dances in the vessel as hydrogen is evolved. 

The primary objective here is to show students how reactive aluminium is.

With an accompanying video, Declan Flemming guides you through the dancing flames experiment, from preparation to demonstration, and discusses how to avoid common problems.