Alkali metals – the camera lies

Alkali 1 shutterstock 159405800 300tb[1]

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Declan Fleming explains how Brainiac's faked explosions helped produce a great resource to stretch his students

What demonstration do you use to teach group relationships in the periodic table? What reaction shows the similarity of elements in a group and also the progressive chemistry from one element to the next?

Alkali metals in water? Yep.

Lithium fizzes, sodium pops, potassium explodes. Of course, it’s not practical to demonstrate rubidium and caesium live – but everyone knows their reactions are progressively more dramatic, and you can just show the video. Right?

With a link to the Braniac video, this article explores how to use their faked explosion as a teaching resource.

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