Oxygen Essay -- essays research papers

group OOxygen and its compounds play a key role in many of the principal(prenominal) processes oflife and industry. Oxygen in the biosphere is essential in the processes ofrespiration and metabolism, the means by which animals derive the energy neededto sustain life. Furthermore, type O is the around abundant element at the surfaceof the Earth. In combined form it is found in ores, earths, rocks, and gemst mavins,as well as in all living organisms. Oxygen is a vaporish chemical element inGroup VA of the periodic table. The chemical symbol for atomic oxygen is O, itsatomic number is 8, and its atomic weight is 15.9994. Elemental oxygen is cognizeprimarily in the gaseous form as the diatomic molecule, which makes up 20.95%of the volume of dry air. Diatomic oxygen is colorless, odorless, and tasteless.Two 18th-century scientists share the reference point for first isolating elementaloxygen Joseph PRIESTLEY (1733-1804), an English clergyman who was employed as aliterary companion to Lord Shelburne at the time of his most significantexperimental work, and Carl Wilhelm SCHEELE (1742-86), a Swedish pharmacist andchemist. It is generally believed that Scheele was the first to isolate oxygen,but that Priestley, who independently achieved the isolation of oxygen somewhatlater, was the first to publicly announce his findings. The interpretation ofthe findings of Priestley and the resultant clarification of the nature ofoxygen as an element was accomplished by the French scientist Antoine-LaurentLAVOISIER (1743-94). Lavoisiers experimental work, which extended and improvedupon Priestleys experiments, was principally responsible for the understandingof COMBUSTION and the establishment of the law of conservation of matter.Lavoisier gave oxygen its name, which is derived from dickens Greek words that mean"acid former." Lavoisier held the mistaken idea that oxides, when turn inwater, would form only acids. It is true that some oxides when dissolved inwater do form acids for example, sulfur dioxide forms sulfurous acid. Someoxides, however, such as sodium oxide, dissolve in water to form bases, as inthe reaction to form sodium hydroxide therefore oxygen was actuallyunsuitably named.NATURAL OCCURRENCEOxygen is formed by a number of nuclear processes that are believed to occur instellar interiors. The most abundant isotope of oxygen, with gage 16,... ... are observed to exist over a range ofcompositions all possessing the same underlying structure. A number of thesetitanium oxides exhibit more than one crystal structure (polymorphism). The mostoxidized compound, titanium, is widely used in the RUTILE form as a whitepigment in paints. Ternary oxides, consisting of two metallic elements plusoxygen, are of great interest to solid-state scientists. For example, compoundssuch as the SPINELS and the PEROVSKITES are studied extensively be prepare of theirinteresting magnetic and electrical properties. Examples of important ternaryoxides are the magnetic FERRITES, whose magnetic properties can be tailored,making them useful in computer memory units. The ferrites are prepared by flakcompacted mixtures of iron oxide and one or more metal oxides (such as those ofnickel, copper, zinc, magnesium, and manganese). Also of importance in inorganicchemistry are the oxides of the nonmetals. Most of the nonmetals are known toform a wide variety of compounds with oxygen. The nitrogen oxides areundesirable by-products of high-temperature combustion in air (as in an internalcombustion engine) and can cause serious environmental pollution.