Search results
Results from the WOW.Com Content Network
Gray arsenic, also called grey arsenic or metallic arsenic, is the most stable allotrope of the element at room temperature, and as such is its most common form. [1] This soft, brittle allotrope of arsenic has a steel gray, metallic color, and is a good conductor. [2] The rhombohedral form of this allotrope is analogous to the phosphorus ...
This unstable allotrope, being molecular, is the most volatile, least dense, and most toxic. Solid yellow arsenic is produced by rapid cooling of arsenic vapor, As 4. It is rapidly transformed into grey arsenic by light. The yellow form has a density of 1.97 g/cm 3. [20] Black arsenic is similar in structure to black phosphorus. [20]
Allotropy. Property of some chemical elements to exist in two or more different forms. Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other' and τρόπος (tropos) 'manner, form') is the property of some ...
Standard atomic weight Ar° (As) 74.921 595 ± 0.000 006[2] 74.922 ± 0.001 (abridged) [3] view. talk. edit. Arsenic (33 As) has 32 known isotopes and at least 10 isomers. Only one of these isotopes, 75 As, is stable; as such, it is considered a monoisotopic element. The longest-lived radioisotope is 73 As with a half-life of 80 days.
Arsenic sublimes at 615 °C. It has a rhombohedral polyatomic crystalline structure (CN 3). Arsenic is a semimetal, with an electrical conductivity of around 3.9 × 10 4 S•cm −1 and a band overlap of 0.5 eV. It has a moderate ionisation energy (947 kJ/mol), moderate electron affinity (79 kJ/mol), and moderate electronegativity (2.18).
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.
You can find instant answers on our AOL Mail help page. Should you need additional assistance we have experts available around the clock at 800-730-2563.
Pnictogen. The pnictogens[1] (/ ˈpnɪktədʒən / or / ˈnɪktədʒən /; from Ancient Greek: πνῑ́γω "to choke" and -gen, "generator") are the chemical elements in group 15 of the periodic table. This group is also known as the nitrogen group or nitrogen family. Group 15 consists of the elements nitrogen (N), phosphorus (P), arsenic (As ...