What a busy hour that was yesterday afternoon! In our Science Masterclass everyone had the chance to make a lava lamp.

There was great excitement at how the water and oil mixed when we were putting the oil in the bottle. We then had to wait until the oil and water had separated before we could add our food colouring. Next we added a small piece of Alka-Seltzer tablet to create the bubbles.

Now for the science bit. Can you remember why the water and oil separate? The oil separates on top of the water because it has a lower density than water. The food colouring falls through the oil and mixes with the water at the bottom of the bottle. The Alka-Seltzer tablet releases small bubbles of carbon dioxide gas that rise to the top taking the coloured water with it. Alka-Seltzer contains citric acid and baking soda which react with the water to form the bubbles.

Remember to show someone at home how it all works. Here are a few photographs from our session. Chloe S was our photographer.