Chemistry Behind How Seawater Buffer or Neutralize Acids are Created

When calcium carbonate reacts with acidic free hydrogen (H⁺) ions in seawater, the solid calcium carbonate dissolves, forming free calcium (Ca²⁺) ions and free bicarbonate (HCO3^–) ions. The free hydrogen ions are consumed resulting in decreased hydrogen ion activity. In other words, calcium carbonate acts to neutralize or buffer the solution by consuming hydrogen ions.

Similarly, calcium and magnesium bicarbonates, which are...

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