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):
  • This system exists in freshwater lakes and rivers.

Structure of carbonic acid

Hydrogen carbonate forms from
the dissolution of salt from rocks