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Magnetic separation is the process of separating components of mixtures by using a magnet to attract magnetic substances. [1] The process that is used for magnetic ...
Minerals that were once thought of as gangue, and were dumped, may later find a commercial use. When this happens, the old dumps are often reworked to extract the wanted mineral. For example, in copper mines in the 19th century the mineral arsenopyrite was dumped until arsenic compounds became popular as insecticides later in the century.
Oxyarsenides or arsenide oxides are chemical compounds formally containing the group AsO, with one arsenic and one oxygen atom. The arsenic and oxygen are not bound together as in arsenates or arsenites, instead they make a separate presence bound to the cations (metals), and could be considered as a mixed arsenide-oxide compound.
A separation process is a method that converts a mixture or a solution of chemical substances into two or more distinct product mixtures, [1] a scientific process of separating two or more substances in order to obtain purity. At least one product mixture from the separation is enriched in one or more of the source mixture's constituents.
Arsenic trioxide powder.. Compounds of arsenic resemble in some respects those of phosphorus which occupies the same group (column) of the periodic table.The most common oxidation states for arsenic are: −3 in the arsenides, which are alloy-like intermetallic compounds, +3 in the arsenites, and +5 in the arsenates and most organoarsenic compounds.
The group 1 alkali metals and the group 2, alkaline earth metals, form arsenides with isolated arsenic atoms. They form upon heating arsenic powder with excess sodium gives sodium arsenide (Na 3 As). The structure of Na 3 As is complex with unusually short Na–Na distances of 328–330 pm which are shorter than in sodium metal.
Inorganic arsenic and its compounds, upon entering the food chain, are progressively metabolized to a less toxic form of arsenic through a process of methylation. [7] Organoarsenic compounds arise via biomethylation of inorganic arsenic compounds, [ 8 ] via processes mediated by enzymes related to vitamin B 12 . [ 9 ]
Arsenic and its compounds, especially the trioxide, are used in the production of pesticides, treated wood products, herbicides, and insecticides. These applications are declining with the increasing recognition of the toxicity of arsenic and its compounds. [15] Arsenic has been known since ancient times to be poisonous to humans. [16]