When carbon dioxide is added to water, the gas adds acidity to the water. The reaction between the Carbon dioxide and the water is a synthesis reaction, sometimes known as a combination reaction, and creates an acid known as Carbonic acid.
In this post I will talk you through Step by Step on how to make Carbonic Acid and the Science of the reaction as we go...What you will need:
- An empty small drinking bottle
- A balloon
- Citric Acid
- Bicarbonate of Soda
- A bowl or a cup
- pH paper
We need to make the gas CO2 Carbon dioxide. To do this add 10ml of citric acid and 10ml of bicarbonate of soda (also known by scientists as sodium hydrogen carbonate) to your empty bottle (I used a conical flask but a small empty bottle of water will work too).
Add 20ml of water to the bottle and quickly put a balloon on the neck of the bottle.
Prepare a cup of a bowl of 100ml of water - I just use tap water.
Test the pH level of the water - it should be 7 which is neutral.
Carefully remove the balloon from the bottle without letting too much of the gas - CO2 - to escape.
Put the neck of the balloon under the water and release the gas slowly into the water.
As the bubbles pass through the water the carbon dioxide mixes with the water.
Test the pH of the water now. It's no longer water, it is now carbonic acid, The pH should read that it's now a mild acid as proof.
The Chemical Equation for this reaction is:
CO2 + H2O -----> H2CO3