The Acidic Environment > 4. Acid/Base Definitions >
Qualitatively describe the effect of buffers with reference to a specific example in a natural system
- Buffer system: A solution that controls its acidity, such that if an acid or a base is added, there is a minimal change in pH.
- A buffer solution is generally a mixture of a weak acid and its conjugate base.
- An example of a buffer system that exists in nature is a solution of carbonic acid (which forms from the dissolution of carbon dioxide from the air) and hydrogen carbonate (which forms from the dissolution of salts from rocks):
![](https://easychem.com.au/wp-content/uploads/2018/04/Natural-Buffer-System.png)
- This system exists in freshwater lakes and rivers.