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You will not exist involved the address to your' Indian attention'. Electrical, Electronics, and Computer Engineering - Advanced. University of levels. Technical University of Hamburg-Harburg. Technical University Berlin. For more need about complete Science , l substantially. Silicon is a dark gray element with a metallic luster. The name of the element is derived from the Latin word for flint, silicis.
In the form of silica SiO 2 or one of the silicates SiO 4 4- , it is found in many different minerals, including clay, quartz, zircon, feldspar, mica, zeolites, aluminosilicates, sand, etc. It is also found in the gemstones opal, agate, rhinestone, and amethyst. Silicon is one of the most important elements on the periodic table at least from the perspective of computers!
Semimetals, Volume 20
Ultrapure silicon doped with boron or phosphorus is used as semiconductors in transistors, which are heavily employed in computers, solar panels, and other applications. Silica which is primarily silicon dioxide, SiO 2 , is used in the manufacture of glass. Silicones, which consist of chains of alternating silicon and oxygen atoms, are used in oils, lubricants, and silicone rubber. Germanium is a hard, grayish white element with a metallic luster. The name of the element is derived from the Latin word for Germany, Germania. It is found in the Earth's crust at a concentration of 2 ppm, making it the 52nd most abundant element.
It is found in the ores argyrodite [Ag 8 GeS 6 ] and germanite [Cu 13 Fe 2 Ge 2 S 16 ], but is more frequently obtained as a by-product of the refining of zinc. Like silicon, germanium is used as a semiconductor, and is widely used in the computer industry. Silicon and germanium are both metalloids , having some characteristics of both metals and nonmetals.
The existence of germanium was predicted by Dimitri Mendeleev in from a blank space in his periodic table beneath silicon; before it was actually found, the hypothetical element was referred to as "eka-silicon. Tin is a soft, silvery-white metal. The name of the element is derived from the Anglo-Saxon word for the metal, while the chemical symbol "Sn" is derived from the Latin name for the metal, stannum.
It is found in the Earth's crust at a concentration of 2 ppm, making it the 49th most abundant element. It is found in the ore cassiterite [tin IV oxide, SnO 2 ], and in trace amounts in other minerals. Structures made of tin that are cooled below Tin is easily purified in its metallic form from its ores, and has been known since prehistoric times.
Semimetals: 1. Graphite and its Compounds - Google Books
Tin is commonly plated onto iron, forming a protective surface that prevents the iron from rusting; this is extremely useful in food containers tin cans because the tin is nontoxic and is not corrosive. Tin can be hammered into thin sheets "tin foil" , but this application has been replaced with aluminum foil.
Bronze has been used since at least BC, since it is harder than copper and more easily made into tools, weapons, works of art, etc. Lead is a very dense, soft, very malleable, bluish-white or grayish metal. The name of the element is derived from the Anglo-Saxon word for the metal, while the chemical symbol "Pb" is derived from the Latin name for the metal, plumbum. It is found in the Earth's crust at a concentration of 14 ppm, making it the 36th most abundant element. Despite its relative rarity, lead has been known since ancient times, since it is comparatively easy to refine and purify.
Lead used to be used in plumbing, since lead pipes don't corrode the way that iron pipes do; the Latin name for lead, plumbum , is also the root of the words "plumbing" and "plumber. Lead is the end product of the radioactive decay of many heavier elements; the ratio of other elements to lead can be used in radioactive dating of rocks.
Lead used to be used to sweeten wine, through the formation of lead IV acetate, Pb C 2 H 3 O 2 4 , also known as "sugar of lead. The earliest pencils used lead, although now "pencil lead" is graphite mixed with clay.
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Lead is a cumulative poison; absorption of lead in the body over a long period of time causes it to be stored in the bones in the form of lead phosphate, where it interferes with the production of hemoglobin, leading to anemia, stomach cramps, constipation, headaches, infertility, etc. Ununquadium is a synthetic element, produced by the fusion of an isotope of plutonium with an isotope of calcium. The longest-lived isotope produced so far, ununquadium, has a half-life of Other isotopes have been produced in other labs, with a wide range of half-lives.
It has been predicted that an isotope having protons and neutrons, ununquadium, should be especially stable, but this isotope has yet to be produced. John Emsley, The Elements , 3rd edition. David L. Heiserman, Exploring Chemical Elements and their Compounds.