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  2. Marine biogenic calcification - Wikipedia

    en.wikipedia.org/wiki/Marine_biogenic_calcification

    The equilibria reactions between these species result in the buffering of seawater in terms of the concentrations of hydrogen ions present. [8] The following chemical reactions exhibit the dissolution of carbon dioxide in seawater and its subsequent reaction with water: CO 2 (g) + H 2 O(l) ⥨ H 2 CO 3 (aq) H 2 CO 3 (aq) ⥨ HCO 3 − (aq) + H ...

  3. Carbonate–silicate cycle - Wikipedia

    en.wikipedia.org/wiki/Carbonate–silicate_cycle

    Two molecules of CO 2 are required for silicate rock weathering; marine calcification releases one molecule back to the atmosphere. The calcium carbonate (CaCO 3) contained in shells and skeletons sinks after the marine organism dies and is deposited on the ocean floor. The final stage of the process involves the movement of the seafloor.

  4. Biological pump - Wikipedia

    en.wikipedia.org/wiki/Biological_pump

    The biological pump (or ocean carbon biological pump or marine biological carbon pump) is the ocean's biologically driven sequestration of carbon from the atmosphere and land runoff to the ocean interior and seafloor sediments. [1]

  5. Calcium carbonate - Wikipedia

    en.wikipedia.org/wiki/Calcium_carbonate

    Calcium carbonate reacts with water that is saturated with carbon dioxide to form the soluble calcium bicarbonate. CaCO 3 (s) + CO 2 (g) + H 2 O(l) → Ca(HCO 3) 2 (aq) This reaction is important in the erosion of carbonate rock, forming caverns, and leads to hard water in many regions. An unusual form of calcium carbonate is the hexahydrate ...

  6. Calcium cycle - Wikipedia

    en.wikipedia.org/wiki/Calcium_cycle

    The calcium cycle is a transfer of calcium between dissolved and solid phases. There is a continuous supply of calcium ions into waterways from rocks, organisms, and soils. [1] [2] Calcium ions are consumed and removed from aqueous environments as they react to form insoluble structures such as calcium carbonate and calcium silicate, [1] [3] which can deposit to form sediments or the ...

  7. Carbonic acid - Wikipedia

    en.wikipedia.org/wiki/Carbonic_acid

    In even a slight presence of water, carbonic acid dehydrates to carbon dioxide and water, which then catalyzes further decomposition. [6] For this reason, carbon dioxide can be considered the carbonic acid anhydride. The hydration equilibrium constant at 25 °C is [H 2 CO 3]/[CO 2] ≈ 1.7×10 −3 in pure water [12] and ≈ 1.2×10 −3 in ...

  8. Microbiologically induced calcite precipitation - Wikipedia

    en.wikipedia.org/wiki/Microbiologically_induced...

    Ammonium and carbonic acid form bicarbonate and 2 moles of ammonium and hydroxide ions in water (3 &4). 2NH 3 + 2H 2 O ↔ 2NH + 4 +2OH − (3) H 2 CO 3 ↔ HCO − 3 + H + (4) The production of hydroxide ions results in the increase of pH, [35] which in turn can shift the bicarbonate equilibrium, resulting in the formation of carbonate ions (5)

  9. Aragonite - Wikipedia

    en.wikipedia.org/wiki/Aragonite

    Aragonite is a carbonate mineral and one of the three most common naturally occurring crystal forms of calcium carbonate (Ca CO 3), the others being calcite and vaterite.It is formed by biological and physical processes, including precipitation from marine and freshwater environments.