The concentration of atmospheric carbon dioxide affects the pH of the ocean and the speciation of carbon in the ocean. This can have profound effects on organisms that form shells, as low carbonate concentrations may reduce their ability to form shells and increased acidity may even cause the shells of marine animals to dissolve.

However, to fully grasp the processes of ocean acidification and carbon speciation, you must gain an understanding of several chemistry concepts. These include:

• Definitions of acids and bases
• Equilibria, reaction quotients and equilibrium constants
• The pH scale
• Strengths of weak acids and bases
• Speciation and the effect of pH on chemical speciation
• Precipitation equilibria and solubility products