Interesting Arsenic Facts

Arsenic is an element that can be found in native state or relatively pure in nature.
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Arsenic is best known as a poison and pigment, but it has many other interesting properties. Here are 10 interesting arsenic element facts.

  1. Arsenic is the element with the symbol As and atomic number 33. It is an example of a metalloid or semimetal, with properties of both metals and nonmetals. It is found in nature as a single stable isotope, arsenic-75. At least 33 radioisotopes have been synthesized. Its most common oxidation states are -3 or +3 in compounds. Arsenic also readily forms bonds with its own atoms.
  1. Arsenic occurs naturally in pure crystalline form and also in several minerals, usually with sulfur or with metals. In pure form, the element has three common allotropes: gray, yellow, and black. Yellow arsenic is a waxy solid that converts into gray arsenic after exposure to light at room temperature. Brittle gray arsenic is the most stable form of the element.
  2. The element name arsenic comes from the ancient Persian word Zarnikh, which means "yellow orpiment". Orpiment is arsenic trisulfide, a mineral that somewhat resembles gold. The Greek word ‘arsenikos’ means potent.
  3. Arsenic is an element known to ancient man and important in alchemy. The pure element was officially isolated in 1250 by Albertus Magnus. Early on, arsenic compounds were added to bronze to increase its hardness, as colorful pigments, and in medicines.
  4. When arsenic is heated, it oxidizes and releases an odor similar to that of garlic. Striking various arsenic-containing minerals with a hammer may also release the characteristic odor.
  1. At ordinary pressure, arsenic, like carbon dioxide, does not melt but sublimes directly into vapor. Liquid arsenic only forms under high pressures.
  2. Arsenic has long been used as a poison, but it's readily detected. Past exposure to arsenic may be assessed by examining hair. Urine or blood tests can assay recent exposure. The pure element and all of its compounds are toxic. Arsenic damages multiple organs, including skin, the gastrointestinal tract, the immune system, reproductive system, nervous system, and excretory system. Inorganic arsenic compounds are considered more toxic than organic arsenic. While high doses can cause a quick death, low dose exposure is also dangerous because arsenic can cause genetic damage and cancer. Arsenic causes epigenetic changes, which are heritable changes that occur without alteration of DNA.
  1. Although the element is toxic, arsenic is widely used. It is a semiconductor doping agent. It adds a blue color to pyrotechnic displays. The element is added to improve sphericity of lead shot. Arsenic compounds are still found in certain poisons, such as insecticides. The compounds are often used to treat wood to prevent degradation by termites, fungi, and mold. Arsenic is used to produce linoleum, infrared-transmitting glass, and as a depilatory (chemical hair remover). Arsenic is added to several alloys to improve their properties.
  2. Despite the toxicity, arsenic has several therapeutic uses. The element is an essential trace mineral for proper nutrition in chickens, goats, rodents, and possibly humans. It may be added to livestock food to help the animals put on weight. It has been used as a syphilis treatment, cancer treatment, and skin bleaching agent. Some species of bacteria can perform a version of photosynthesis that uses arsenic rather than oxygen, in order to obtain energy.
  3. The element abundance of arsenic in the Earth's crust is 1.8 parts per million by weight. Approximately a third of the arsenic found in the atmosphere comes from natural sources, such as volcanoes, but most of the element comes from human activities, such as smelting, mining (especially copper mining), and release from coal-burning power plants. Deep water wells are commonly contaminated with arsenic.