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Magnesium oxide (Mg O), 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 Mg 2+ ions and O 2− ions held together by ionic bonding .
In both, magnesium oxide is the precursor to magnesium metal. The magnesium oxide is produced as a solid solution with calcium oxide by calcining the mineral dolomite, which is a solid solution of calcium and magnesium carbonates: CaCO 3 ·MgCO 3 → MgO·CaO + 2 CO 2. Reduction occurs at high temperatures with silicon.
Crystalline magnesium oxide, or periclase, has a calculated lattice energy of 3795 kJ mol-1 which must be overcome for it to go into solution or for reaction to occur. Reactive magnesia is essentially amorphous magnesia with low lattice energy and is made at low temperatures and finely ground.
Magnesium oxide is the end product of the thermal decomposition of some magnesium compounds and is usually prepared by igniting carbonates or hydroxides. Magnesium hydroxide is a strong electrolyte, which can be obtained by the reaction of a soluble magnesium salt and sodium hydroxide.
Specially activated magnesium, such as Rieke magnesium, circumvents this problem. [5] The oxide layer can also be broken up using ultrasound, using a stirring rod to scratch the oxidized layer off, [6] or by adding a few drops of iodine or 1,2-Diiodoethane. Another option is to use sublimed magnesium or magnesium anthracene. [7]
Equations that apply in one picture do not necessarily hold in the others, because time-dependent unitary transformations relate operators in one picture to the analogous operators in the others. Not all textbooks and articles make explicit which picture each operator comes from, which can lead to confusion.
Magnesium nitride reacts with water to produce magnesium hydroxide and ammonia gas, as do many metal nitrides.. Mg 3 N 2 (s) + 6 H 2 O(l) → 3 Mg(OH) 2 (aq) + 2 NH 3 (g). In fact, when magnesium is burned in air, some magnesium nitride is formed in addition to the principal product, magnesium oxide.
Magnesium nitrate reacts with alkali metal hydroxide to form the corresponding nitrate: Mg(NO 3) 2 + 2 NaOH → Mg(OH) 2 + 2 NaNO 3.. Since magnesium nitrate has a high affinity for water, heating the hexahydrate does not result in the dehydration of the salt, but rather its decomposition into magnesium oxide, oxygen, and nitrogen oxides: