The Effects Of Ocean Acidification

Acidification of the Oceans

Better known as the other CO2 problem; ocean acidification, is the increase in acidity of the oceans due to vast amounts of anthropogenic carbon dioxide being released into the atmosphere. An increase in the atmospheric carbon dioxide concentration is resulting in an increased the amount of carbon dioxide being dissolved into the oceans. The planet’s carbon sink currently absorbs around 1/3 of the carbon dioxide released into atmosphere, that’s 22 million tons of carbon dioxide being dissolved into our oceans every day! Although this is reducing the carbon dioxide levels in atmosphere and its effects, a huge price is being paid in form of a rapid change in the chemistry of the oceans; which are home to 94% life on

Le Chatelier’s Principle states “if a dynamic equilibrium is disturbed by changing the conditions, the position of the equilibrium moves to counteract the change”- chemguide.co.uk. Currently, massive amounts of CO2(g) (reactant) is being released into the atmosphere and hence increasing its concentration in the equilibrium, so the position of the equilibrium will move to the right in favour of CO2(aq) (product) to counteract the change by decreasing the concentration of the CO2(g). Hence an increase in the amount of CO2 released into the atmosphere increases the amount of it absorbed by the

As more and more CO2 is being dissolved into the oceans, the H+ ion concentration is experiencing a large proportional increase. This increase in the H+ ion concentration results in an equilibrium shift to the right to reduce the H+ ion concentration, and thus increasing the concentration of the bicarbonate ions. At the same time, more CO32- ions are being required to neutralise the H+ ions due to their increase in concentration. Although, CO32- ions experience a small proportional increase in their concentration due to more CO2 being dissolved into the ocean, the amount of CO32- ions required to neutralise the H+ ions is far greater than the small increase experienced by the CO32- ions. So, more CO32- are required to neutralise the H+ ions in the buffer reaction to resist the change in pH, thus resulting in a decrease in concentration of the CO32- ions in the oceans! A large proportion of the H+ ions are neutralised by this reaction, but some remain dissolved in water. As the H+ ions experience a large proportional increase, so does the quantity of the small proportion ions that stay dissolved in water, hence increasing the concentration of the H+ ions in the water. pH is a logarithm scale that measures the concentration of the H+ ions in a body and it’s defined as: –log[H+]. So, as the concentration of the H+ ions that stay dissolved in the