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When administered intravenously, a steady state is reached after 8–10 days. Arsenic binds to proteins to an insignificant extent. The highest concentrations of arsenic are found in the liver, kidneys, heart, lungs, hair, and nails. Arsenous acid is oxidized to arsenic acid and methylated in the liver, [65] [66] [67] and then excreted 60% in ...
It is rapidly transformed into grey arsenic by light. The yellow form has a density of 1.97 g/cm 3. [23] Black arsenic is similar in structure to black phosphorus. [23] Black arsenic can also be formed by cooling vapor at around 100–220 °C and by crystallization of amorphous arsenic in the presence of mercury vapors. [26] It is glassy and ...
The Marsh test treats the sample with sulfuric acid and arsenic-free zinc. Even if there are minute amounts of arsenic present, the zinc reduces the trivalent arsenic (As 3+). Here are the two half-reactions: Oxidation: Zn → Zn 2+ + 2 e − Reduction: As 2 O 3 + 12 e − + 6 H + → 2 As 3− + 3 H 2 O. Overall, we have this reaction:
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.
Illustrative is the roasting of orpiment, a typical arsenic sulfide ore. 2 As 2 S 3 + 9 O 2 → 2 As 2 O 3 + 6 SO 2. Most arsenic oxide is, however, obtained as a volatile by-product of the processing of other ores. For example, arsenopyrite, a common impurity in gold- and copper-containing ores, liberates arsenic trioxide upon heating in air.
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]
The arsenic (As) cycle is the biogeochemical cycle of natural and anthropogenic exchanges of arsenic terms through the atmosphere, lithosphere, pedosphere, hydrosphere, and biosphere. Although arsenic is naturally abundant in the Earth's crust, long-term exposure and high concentrations of arsenic can be detrimental to human health. [1] [2]
It was first isolated from the New Caledonian marine sponge Echinochalina bargibanti. [1] 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 ...