Today in science we were learning about mixtures. A mixture is a selection of items that are put together and there is no chemical reaction. The items can be separated back out to their original form.

We made lava lamps with water, cooking oil and effervescent vitamin C tablets. First we filled a test tube three quarters of the way with cooking oil. Then we added water and left a two cm gap at the top. We noticed that the water and the oil separated with the water at the bottom and the cooking oil at the top. This is because the cooking oil is less dense than the water. Next we added in the tablet. We observed that the tablet did not react in the oil but when it reached the water there was a chemical reaction where carbon dioxide was produced. This gas attached to small amounts of water pushing it though the oil.

by Iona Shanks