Nitrogen, which makes up about 78% of our atmosphere, is a colorless, odorless, tasteless and chemically unreactive gas at room temperature. It is named from the Greek nitron + genes for soda forming. Discovered in 1772 by Daniel Rutherford (and independently by others such as Priestly and Cavendish), it is more abundant in the known universe than carbon or silicon. Most commercially produced nitrogen gas is recovered from liquefied air. Of that amount, the majority is used to manufacture ammonia (NH3) via the Haber process. Much is also converted to nitric acid (HNO3). Small amounts of nitrogen (for laboratory study) can be prepared by heating solid ammonium chloride (NH4Cl) with solid ammonium nitrite (NH4NO2). Sodium chloride and water are by-products. Nitrogen forms a surprising number of compounds with oxygen, exhibiting a wide range of oxidation states. Some of the more familiar ones include nitrogen dioxide (NO2), a component of photochemical smogs and a contributor to acid rain in some areas, and dinitrogen monoxide (N2O) commonly called "laughing gas".Named from the Greek word phosphorus ("bringer of light"), phosphorus was first isolated in 1669 by Hennig Brand (a painting commemorating this achievement is in the rotating gallery that appears on the home page of this site). The original extraction was made from about 60 pails of urine..... Industrial processes for isolating phosphorus today involve heating calcium phosphate, carbon and silicon dioxide. Phosphorus occurs in at least 10 allotropic forms, the most common (and reactive) of which is so-called white (or yellow) phosphorus which looks like a waxy solid or plastic. It is very reactive and will spontaneously inflame in air so it is stored under water. The other common form of phosphorus is red phosphorus which is much less reactive and is one of the components on the striking surface of a match book. Red phosphorus can be converted to white phosphorus by careful heating. Commercially, phosphorus compounds are used in the manufacture of phosphoric acid (H3PO4) (found in soft drinks and used in fertilizer compounding). Other compounds find applications in fireworks and, of course, phosphorescent compounds which glow in the dark.
Arsenic has been known for a very long time and the person who may have first isolated it is not known but credit generally is given to Albertus Magnus in about the year 1250. The element, which is classified as a metalloid, is named from the Latin arsenicum and Greek arsenikon which are both names for a pigment, yellow orpiment. Tiny amounts of arsenic are used today in the semiconductor industry to create LEDs. Some compounds are used in the manufacture of everything from wallpaper to ceramics. Of course, arsenic is most often thought of in terms of its toxicity and it is used as a weed killer and rat poison. Intentional arsenic poisoning is now pretty much the stuff of old murder mysteries. Originally arsenious oxide was administered in small doses over a period of time, precipitating death accompanied by symptoms reminiscent of pneumonia. Today the arsenic remaining in the body can be detected during autopsy so this is not (happily) a very effective way to dispatch people undetected. Commercially, arsenic is produced by heating the pigment orpiment (As2S3) in air and then reacting the oxide product with carbon.
Antimony and its compounds have been known for centuries. Scientific study of the element began during the early 17th century, much of the important work being done by Nicolas Lemery. The name of the element comes from the Greek anti + monos for "not alone", while the modern symbol is rooted in the Latin-derived name of the common ore, stibnite. Antimony is a hard, brittle metalloid which is alloyed with other metals to increase hardness. It is also used in some semi-conductor devices. The recovery of elemental antimony parallels that of arsenic: the sulfide ore (stibnite) is roasted in air and then heated with carbon.
Bismuth, the heaviest non-radioactive naturally occurring element, was isolated by Basil Valentine in 1450. It is a hard, brittle metal with an unusually low melting point (271oC). Alloys of bismuth with other low-melting metals such as tin and lead have even lower melting points and are used in electrical solders, fuse elements and automatic fire sprinkler heads. The metal can be found in nature, often combined with copper or lead ores, but can also be extracted from bismuth (III) oxide by roasting with carbon. Compounds of bismuth are used in pigments for oil painting and one is in a popular pink preparation for the treatment of common stomach upset.
In studies announced jointly by the Joint Institute for Nuclear Research in Dubna, Russia, and the Lawrence Livermore National Laboratory in the U.S., four atoms of element 113 were produced in 2004 via decay of element 115 after the fusion of Ca-48 and Am-243.
Dr.Badruddin Khan teaches Chemistry in the University of Kashmir, Srinagar, India.
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