BackConsider the reaction between carbon dioxide and water to form carbonic acid (CH2O3):
CO2(𝑔)+H2O(𝑙)⇌CH2O3(𝑎𝑞)
In the ocean, carbonic acid immediately dissociates to form a proton and bicarbonate ion, as follows:
CH2O3(𝑎𝑞)⇌CHO3−(𝑎𝑞)+H+(𝑎𝑞)
As atmospheric CO2 increases, the ocean absorbs more of the gas. Would this sequence of reactions be driven to the left or the right? How would this affect the pH of the ocean?
Stony corals secrete thin layers of calcium carbonate (CaCO3) to build the foundation of coral reefs. The relationship between calcium carbonate, carbonic acid, and calcium bicarbonate (Ca(HCO3)2) is shown below:
CH2O3(𝑎𝑞)+CaCO3(𝑠) ⇌ Ca(HCO3)2(𝑎𝑞)
Predict what will happen to the calcium carbonate foundation of reefs as CO2 levels rise in the oceans.
The current average pH of our oceans is 8.1. What is the concentration of protons in the oceans? How has the proton concentration changed in our oceans when compared to before the industrial revolution, when the average pH was 8.2? Express this change as a percentage increase.