Short videos of exciting demonstrations of the chemistry of everyday materials, taken from a lecture by Peter Wothers at the University of Cambridge.

Free Range Chemistry: 24 - Limestone

What is limestone made of, and how can we tell?

Free Range Chemistry: 25 - Shells

Shells and limestone have a lot in common - both contain lots of calcium carbonate!

Free Range Chemistry: 26 - Importance of Calcium

See what would happen if there was no calcium in our bones!

Free Range Chemistry: 27 - Exploding Rock

Pouring water on calcium oxide has a very dramatic effect!

Free Range Chemistry: 28 - Calcium and Water

Find out why we never find calcium metal in nature.

Free Range Chemistry: 29 - Wood ash

Extracting potassium carbonate from ashes.

Free Range Chemistry: 30 - Potassium from Potash

A clever reaction to make potassium from potash.

Free Range Chemistry: 31 - Potassium and Water

Violent reaction of potassium metal with water!