Rubber Egg

 

The shell of an egg is made from calcium carbonate. This reacts with vinegar, which is an acid, in a similar way to bicarbonate of soda, that we have seen in other experiments, like making volcanoes or bath bombs. Look at the Natural Indicator activity to learn more about acids

The first thing that you need to do is put your egg in your glass or container. You may need to use a spoon to help you with this.

You now want to cover it with vinegar. You will see that a reaction starts to happen as soon as you start to add the vinegar. You will see bubbles start to form on the surface of the egg. These are bubbles of carbon dioxide.

You will want to leave your egg in the vinegar for a few days. You will see that the shell of the egg becomes completely dissolved. 

The vinegar reacts with the calcium carbonate in the egg shell, producing carbon dioxide bubbles and dissolving the shell. Once the shell has gone, the outer membrane becomes tougher as the vinegar moves into the egg by osmosis, pickling the egg and hardening it. This gives the egg its rubber texture and allows you to bounce or roll it, without breaking it.

The video tutorial for this activity is available on the Surrey Libraries Facebook Page or YouTube Channel