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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]
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 carbonates bind to plumbing surfaces providing seed crystals for further crystal growth, which build up as hard scale. [citation needed] Physical water treatment (PWT) devices cause microscopic mineral crystals to form and remain suspended as they flow with the water, while also acting as seeds for further crystal growth. As water is heated ...
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]
It represents the pentahydrate of magnesium carbonate, and has the total formula MgCO 3 ·5H 2 O . [2] Landsfordite was discovered in 1888 in a coal mine in Lansford, Pennsylvania. It crystallizes in the monoclinic system (space group P2 1 /c [3]) and typically occurs as colorless to white prismatic crystals and stalactitic masses. [4]
The most widely used anticaking agents include the stearates of calcium and magnesium, silica and various silicates, talc, as well as flour and starch. Ferrocyanides are used for table salt. [ 1 ] The following anticaking agents are listed in order by their number in the Codex Alimentarius by the Food and Agriculture Organization of the UN.
It occurs principally in combination as oxides, of which the chief are silica, alumina, iron oxides, and various carbonates (calcium carbonate, magnesium carbonate, sodium carbonate, and potassium carbonate). The silica functions principally as an acid, forming silicates, and all the commonest minerals of igneous rocks are of this nature.