This week, the Maths STEM club created lava lamps in bottles. The pupils dissolved Alka-Seltzer tablets in water mixed with food colouring. This generated coloured, carbon dioxide bubbles that slowly floated upwards through an oil layer. We discussed why oil doesn’t mix with water, bringing in a topic taught in Maths (density, mass and volume) and the real-life applications of carbon dioxide (such as in fizzy drinks and fire extinguishers).
