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Arsenic is added in small quantities to alpha-brass to make it dezincification-resistant. This grade of brass is used in plumbing fittings and other wet environments. [110] Arsenic is also used for taxonomic sample preservation. It was also used in embalming fluids historically. [111] Arsenic was used in the taxidermy process up until the 1980s ...
In its standard state arsine is a colorless, denser-than-air gas that is slightly soluble in water (2% at 20 °C) [1] and in many organic solvents as well. [citation needed] Arsine itself is odorless, [5] but it oxidizes in air and this creates a slight garlic or fish-like scent when the compound is present above 0.5 ppm. [6]
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
Another allotrope of carbon is a fullerene, which has the form of sheets of carbon atoms folded into a sphere. A fifth allotrope of carbon, discovered in 2003, is called graphene, and is in the form of a layer of carbon atoms arranged in a honeycomb-shaped formation. [6] [14] [15] Silicon has two known allotropes that exist at room temperature.
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]
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.
The compound was characterized by computational and spectroscopic [2] [3] techniques and found to possess a cage-like structure similar to adamantane in which the four methanetriyl carbon bridgeheads are replaced by arsenic atoms and three of the six methylene bridges are replaced by oxygen atoms.
Perey discovered it as a decay product of 227 Ac. [177] Francium was the last element to be discovered in nature, rather than synthesized in the lab, although four of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine, and promethium) were eventually found in trace amounts in nature as well. [178]