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Magnesium carbonate is ordinarily obtained by mining the mineral magnesite. Seventy percent of the world's supply is mined and prepared in China. [9] Magnesium carbonate can be prepared in laboratory by reaction between any soluble magnesium salt and sodium bicarbonate: MgCl 2 (aq) + 2 NaHCO 3 (aq) → MgCO 3 (s) + 2 NaCl(aq) + H 2 O(l) + CO 2 (g)
Magnesite can also be formed via the carbonation of magnesium serpentine (lizardite) via the following reaction: 2 Mg 3 Si 2 O 5 (OH) 4 + 3 CO 2 → Mg 3 Si 4 O 10 (OH) 2 + 3 MgCO 3 + 3 H 2 O. However, when performing this reaction in the laboratory, the trihydrated form of magnesium carbonate (nesquehonite) will form at room temperature. [6]
It is the most common cave carbonate after calcite and aragonite. [2] The mineral thermally decomposes, [5] [6] over a temperature range of approximately 220 °C to 550 °C, releasing water and carbon dioxide leaving a magnesium oxide residue. Hydromagnesite was first described in 1836 for an occurrence in Hoboken, New Jersey. [3]
Resins are also available to remove the carbonate, bicarbonate, and sulfate ions that are absorbed and hydroxide ions that are released from the resin. [ 9 ] When all the available Na + ions have been replaced with calcium or magnesium ions, the resin must be recharged by eluting the Ca 2+ and Mg 2+ ions using a solution of sodium chloride or ...
Like magnesium oxide, it will generate a basic carbonate when placed in the air. [3] Magnesium sulfide can be produced by the reaction of magnesium and hydrogen sulfide, or by the reaction of magnesium sulfate and carbon disulfide at high temperature: [6] Mg + H 2 S → MgS + H 2 3 MgSO 4 + 4 CS 2 → 3 MgS + 4 COS + 4 SO 2
The reaction of magnesium carbonate with the free alkali hydroxides present in the cement porewater also leads to the formation of expansive brucite. MgCO 3 + 2 NaOH → Mg(OH) 2 + Na 2 CO 3. This reaction, one of the two main alkali–aggregate reaction (AAR) is also known as alkali–carbonate reaction.
In chemistry, fractional crystallization is a stage-wise separation technique that relies on the liquid–solid phase change. This technique fractionates via differences in crystallization temperature and enables the purification of multi-component mixtures, as long as none of the constituents can act as solvents to the others.
The key steps involved in marine biogenic calcification include the uptake of dissolved calcium ions (Ca 2+) and carbonate ions (CO 3 2-) from seawater, the precipitation of calcium carbonate crystals, and the controlled formation of skeletal structures through biomineralization processes.