Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column of the periodic table: all group 2 elements have the same electron configuration in the outer electron shell and a similar crystal structure.
In chemistry, a silicate is any member of a family of anions consisting of silicon and oxygen, usually with the general formula [SiO(4−2x)−
4−x]
n, where 0 ≤ x < 2. The family includes orthosilicate SiO4−
4, metasilicate SiO2−
3, and pyrosilicate Si
2O6−
7. The name is also used for any salt of such anions, such as sodium metasilicate; or any ester containing the corresponding chemical group, such as tetramethyl orthosilicate.
The mineral olivine is a magnesium iron silicate with the chemical formula (Mg2+, Fe2+)2SiO4. It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation. Olivine also has many other historical uses, such as the gemstone peridot (or chrysolite), as well as industrial applications like metalworking processes.
Magnesium oxide (MgO), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of MgO and consists of a lattice of Mg2+ ions and O2− ions held together by ionic bonding. Magnesium hydroxide forms in the presence of water (MgO + H2O → Mg(OH)2), but it can be reversed by heating it to remove moisture.
Magnesium hydroxide is the inorganic compound with the chemical formula Mg(OH)2. It occurs in nature as the mineral brucite. It is a white solid with low solubility in water (Ksp = 5.61×10−12). Magnesium hydroxide is a common component of antacids, such as milk of magnesia.
Magnesium sulfate or magnesium sulphate is a chemical compound, a salt with the formula MgSO
4, consisting of magnesium cations Mg2+
and sulfate anions SO2−
4. It is a white crystalline solid, soluble in water but not in ethanol.
Magnesium is an essential element in biological systems. Magnesium occurs typically as the Mg2+ ion. It is an essential mineral nutrient (i.e., element) for life and is present in every cell type in every organism. For example, ATP (adenosine triphosphate), the main source of energy in cells, must bind to a magnesium ion in order to be biologically active. What is called ATP is often actually Mg-ATP. As such, magnesium plays a role in the stability of all polyphosphate compounds in the cells, including those associated with the synthesis of DNA and RNA.
Magnesium carbonate, Mg CO3 (archaic name magnesia alba), is an inorganic salt that is a white solid. Several hydrated and basic forms of magnesium carbonate also exist as minerals.
Magnesium chloride is the name for the chemical compound with the formula MgCl2 and its various hydrates MgCl2(H2O)x. Anhydrous MgCl2 contains 25.5% elemental magnesium by mass. These salts are typical ionic halides, being highly soluble in water. The hydrated magnesium chloride can be extracted from brine or sea water. In North America, magnesium chloride is produced primarily from Great Salt Lake brine. It is extracted in a similar process from the Dead Sea in the Jordan Valley. Magnesium chloride, as the natural mineral bischofite, is also extracted (by solution mining) out of ancient seabeds, for example, the Zechstein seabed in northwest Europe. Some magnesium chloride is made from solar evaporation of seawater. Anhydrous magnesium chloride is the principal precursor to magnesium metal, which is produced on a large scale. Hydrated magnesium chloride is the form most readily available.
Peridotite ( PERR-ih-doh-tyte, pə-RID-ə-) is a dense, coarse-grained igneous rock consisting mostly of the silicate minerals olivine and pyroxene. Peridotite is ultramafic, as the rock contains less than 45% silica. It is high in magnesium (Mg2+), reflecting the high proportions of magnesium-rich olivine, with appreciable iron. Peridotite is derived from Earth's mantle, either as solid blocks and fragments, or as crystals accumulated from magmas that formed in the mantle. The compositions of peridotites from these layered igneous complexes vary widely, reflecting the relative proportions of pyroxenes, chromite, plagioclase, and amphibole.
Forsterite (Mg2SiO4; commonly abbreviated as Fo; also known as white olivine) is the magnesium-rich end-member of the olivine solid solution series. It is isomorphous with the iron-rich end-member, fayalite. Forsterite crystallizes in the orthorhombic system (space group Pbnm) with cell parameters a 4.75 Å (0.475 nm), b 10.20 Å (1.020 nm) and c 5.98 Å (0.598 nm).
Magnesium deficiency is an electrolyte disturbance in which there is a low level of magnesium in the body. It can result in multiple symptoms. Symptoms include tremor, poor coordination, muscle spasms, loss of appetite, personality changes, and nystagmus. Complications may include seizures or cardiac arrest such as from torsade de pointes. Those with low magnesium often have low potassium.
Silicon disulfide is the inorganic compound with the formula SiS2. Like silicon dioxide, this material is polymeric, but it adopts a 1-dimensional structure quite different from the usual forms of SiO2.
Belite is an industrial mineral important in Portland cement manufacture. Its main constituent is dicalcium silicate, Ca2SiO4, sometimes formulated as 2 CaO · SiO2 (C2S in cement chemist notation).
Magnesium citrate is a magnesium preparation in salt form with citric acid in a 1:1 ratio. The name "magnesium citrate" is ambiguous and sometimes may refer to other salts such as trimagnesium citrate which has a magnesium:citrate ratio of 3:2.
Tetramethyl orthosilicate is the chemical compound with the formula Si(OCH3)4. This molecule consists of four methoxy groups bonded to a silicon atom. The basic properties are similar to the more popular tetraethyl orthosilicate, which is usually preferred because the product of hydrolysis, ethanol, is less toxic than methanol.
A carbon dioxide scrubber is a piece of equipment that absorbs carbon dioxide. It is used to treat exhaust gases from industrial plants or from exhaled air in life support systems such as rebreathers or in spacecraft, submersible craft or airtight chambers. Carbon dioxide scrubbers are also used in controlled atmosphere (CA) storage. They have also been researched for carbon capture and storage as a means of combating climate change.
In chemistry, orthosilicate is the anion SiO4−
4, or any of its salts and esters. It is one of the silicate anions. It is occasionally called the silicon tetroxide anion or group.
Sodium orthosilicate is the chemical compound with the molecular formula Na
4SiO
4. It is one of the sodium silicates, specifically an orthosilicate, formally a salt of the unstable orthosilicic acid H
4SiO
4.
Lithium orthosilicate is a compound with the chemical formula Li4SiO4. It is a white ceramic compound, which melts congruently at a temperature of 1,258 °C (2,296 °F).
