As part of Science Week students learnt how to make lava lamps out of water, oil and an effervescing tablet. They saw that polar and non-polar solutions do not mix and that water would sink to the bottom of a bottle containing oil and water. The water could be dyed using food colouring without affecting the non-polar oil at the top of the bottle.
Dropping an alka seltzer tablet into the bottle would then cause bubbles of carbon dioxide to rise through the liquid, surrounded by the coloured water and creating a mesmerising lava lamp effect. A little glitter added an extra bit of glamour to their homemade lava lamps.