When some substances are mixed together a reaction occurs. A new material forms and the change that has taken place is irreversible. How can this be proved?
What You Will Need
- A clear empty plastic bottle. (About 0.5l is ideal.).
- A balloon
- Vinegar
- Baking soda (bicarbonate of soda)
- Goggles
What To Do
- Put a teaspoon of baking powder in the plastic bottle.
- Add about 100ml of vinegar.
- Quickly stretch the balloon over the top of the bottle.
What Happens
The baking soda reacts with the vinegar and fizzes. The balloon should inflate with the gas that is produced. The gas (carbon dioxide) is a new material created by the reaction. This is a chemical change, and unlike making a solution, which is a physical change, it is not at all easy to reverse.
You can experiment with other materials.
For the liquid you could try Coke or a citric acid solution.
For the solid, you could try icing sugar or Refreshers.
Alka Seltzers in water react very well.
Care should be taken when experimenting. Balloons can burst or leak, making a mess. All the materials mentioned above are perfectly safe with sensible precautions such as wearing goggles. Experimenting with other substances could produce more extreme reactions. Certainly, never experiment with household cleaning materials.
