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En-en adult card 23 hindered calcification process: Difference between revisions
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En-en adult card 23 hindered calcification process (view source)
Revision as of 20:10, 8 February 2021
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== Explanation == | == Explanation == | ||
The constitution of limestone (calcification) is the following chemical reaction: Ca<sup>++</sup> + 2HCO<sub>3</sub>- ⇔ CaCO<sub>3</sub> + H<sub>2</sub>O + CO<sub>2</sub> | |||
It requires the presence of bicarbonate HCO3- ions. However, the quantity of these ions in water depends on the pH: In water, carbon dioxide, carbonic acid, bicarbonate ion and carbonate ion are in equilibrium, depending on the pH : | |||
CO<sub>2</sub> + H<sub>2</sub>O ⇔ H<sub>2</sub>CO<sub>3</sub> ⇔ H<sup>+</sup> + HCO<sub>3</sub><sup>-</sup> ⇔ 2 H<sup>+</sup> + CO<sub>3</sub><sup>2-</sup>. | |||
The addition of an acid shifts the equilibrium to the left. | |||
In other words, if the pH drops, the bicarbonate ions are in less quantity. Hence the difficulty of making limestone for the organisms that need it. | |||