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Arsenate readily reacts with metals to form arsenate metal compounds. [2] [3] Arsenate is a moderate oxidizer and an electron acceptor, with an electrode potential of +0.56 V for its reduction to arsenite. [4] Due to arsenic having the same valency and similar atomic radius to phosphorus, arsenate shares similar geometry and reactivity with ...
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.
Arsenate (+5 oxidation state) is the dominant form of arsenic in surface water, while arsenite (+3 oxidation state) is the dominant form in hypoxic to anoxic environments. Arsenite is more soluble and mobile than arsenate. Many species of bacteria can transform arsenite to arsenate in anoxic conditions by using arsenite as an electron donor. [189]
IUPAC have recommended that arsenite compounds are to be named as arsenate(III), for example ortho-arsenite is called trioxidoarsenate(III). Ortho-arsenite contrasts to the corresponding anions of the lighter members of group 15, phosphite which has the structure HPO 2− 3 and nitrite, NO − 2 which is bent. [1]
An arsenate arsenite is a chemical compound or salt that contains arsenate and arsenite anions (AsO 3 3-and AsO 4 3-). These are mixed anion compounds or mixed valence compounds. Some have third anions. Most known substances are minerals, but a few artificial arsenate arsenite compounds have been made. Many of the minerals are in the Hematolite ...
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).
Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the (AsO 4) 3− anion group and, more rarely, other arsenates with anions like AsO 3 (OH) 2− (also written HAsO 4 2−) (example: pharmacolite Ca(AsO 3 OH). 2H 2 O) or (very rarely) [AsO 2 (OH) 2] − (example: andyrobertsite). Arsenite minerals are much ...
Calcium arsenate is commonly prepared from disodium hydrogen arsenate and calcium chloride: 2 Na 2 H[AsO 4] + 3 CaCl 2 → 4 NaCl + Ca 3 [AsO 4] 2 + 2 HCl. In the 1920s, it was made in large vats by mixing calcium oxide and arsenic oxide. [6] In the United States, 1360 metric tons were produced in 1919, 4540 in 1920, and 7270 in 1922. [1]