Chapter 17, Problem 128E

Carbon dioxide dissolves in water according to the equations:

   ${\text{CO}}_2(g)+{\text{H}}_2\text{O(}l\text{)}\rightleftharpoons {\text{H}}_2{\text{CO}}_3(aq)$

   ${\text{H}}_2{\text{CO}}_3(g)+{\text{H}}_2\text{O(}l\text{)}\rightleftharpoons {\text{HCO}}_3^{-}(aq)+{\text{H}}_3{\text{O}}^{+}(aq)$

Carbon dioxide levels in the atmosphere have increased about 20% over the last century. Given that Earth’s oceans are exposed to atmospheric carbon dioxide, what effect might the increased CO₂ have on the pH of the world’s oceans? What effect might this change have on the limestone structures (primarily CaCO₃) of coral reefs and marine shells?