Continuing from their examination of bath bombs and hand warmers, the Chemistry Club turned their attention to lava lamps, made using household items like water and oil.
Water and oil do not mix because water is a polar molecule -- its chemical structure means that it is slightly positively charged on one end, and slightly negatively charged on the other. In contrast, oil is non-polar -- its charge is more evenly spread, so the oil is not attracted to the water.
The students coloured the water with their choice of food dye, then added an effervescent tablet to the mixture. This formed carbon dioxide which carried the coloured water to the top. The young chemists had a fantastic time watching the vibrant reactions take place!