Irreversible changes!

In our science topic this half term, Year 5 have been looking at the properties of materials. In our final lesson of the topic today, we carried out an experiment to see if we could create an irreversible change and create a new material. We filled plastic bottles with different amounts of vinegar, before securing a balloon to the top of the bottle which contained bicarbonate of soda. As the bicarbonate of soda mixed in with the vinegar, it created a gas which resulted in our balloons getting inflated. When they had stopped inflating, we removed the balloon, tied it in a knot and measured around the circumference of the balloon with string to see which bottle had created the most gas. We came to the conclusion that the bottle with the most vinegar created the most gas as this balloon had inflated the most. The children loved the experiment and were fantastic at making predictions and recording their results!