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Arsenic is a common n-type dopant in semiconductor electronic devices. It is also a component of the III–V compound semiconductor gallium arsenide. 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 ...
Arsenic compounds have been known for at least 5000 years, and the ancient Greek Theophrastus recognized the arsenic minerals called realgar and orpiment. Elemental arsenic was discovered in the 13th century by Albertus Magnus. [14] Antimony was well known to the ancients. A 5000-year-old vase made of nearly pure antimony exists in the Louvre.
In 1787, German physician Johann Metzger (1739-1805) discovered that if arsenic trioxide were heated in the presence of carbon, the arsenic would sublime. [4] This is the reduction of As 2 O 3 by carbon: 2 As 2 O 3 + 3 C → 3 CO 2 + 4 As
The total number of unique species, including distinct ionization states, is indicated in each section header. Most of the molecules detected so far are organic. The only detected inorganic molecule with five or more atoms is SiH 4. [14] Molecules larger than that all have at least one carbon atom, with no N−N or O−O bonds. [14]
To give provisional names to his predicted elements, Dmitri Mendeleev used the prefixes eka- / ˈ iː k ə-/, [note 1] dvi- or dwi-, and tri-, from the Sanskrit names of digits 1, 2, and 3, [3] depending upon whether the predicted element was one, two, or three places down from the known element of the same group in his table.
Arsenic is a metalloid with an atomic number of 33, and its common oxidation states are +3 or +5, as arsenate(As III) and arsenite(As V). [12] Arsenic is primarily found as organic arsenic compounds, inorganic arsenic compounds, and arsine gas.
These are called theoretical elements. They can have article and other content pages though. They can have article and other content pages though. Incidentally, this concerns period 8 completely.
Arsenic forms colorless, odorless, crystalline oxides As 2 O 3 ("white arsenic") and As 2 O 5 which are hygroscopic and readily soluble in water to form acidic solutions. Arsenic(V) acid is a weak acid and the salts are called arsenates , [ 5 ] the most common arsenic contamination of groundwater , and a problem that affects many people.