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17 hours ago · Five nonmetals—hydrogen, carbon, nitrogen, oxygen, and silicon—form the bulk of the directly observable structure of the Earth: about 73% of the crust, 93% of the biomass, 96% of the hydrosphere, and over 99% of the atmosphere, as shown in the accompanying table. Silicon and oxygen form highly stable tetrahedral structures, known as ...
17 hours ago · WSF. Zeitgeist. v. t. e. Transhumanism is a philosophical and intellectual movement that advocates the enhancement of the human condition by developing and making widely available new and future technologies that can greatly enhance longevity, cognition, and well-being. [1] [2] [3] Transhumanist thinkers study the potential benefits and dangers ...
17 hours ago · Molybdenum is the 54th most abundant element in the Earth's crust with an average of 1.5 parts per million and the 25th most abundant element and most abundant transition metal in the oceans, with an average of 10 parts per billion; it is the 42nd most abundant element in the Universe.
17 hours ago · Iridium is a chemical element; it has symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, it is considered the second-densest naturally occurring metal (after osmium) with a density of 22.56 g/cm 3 (0.815 lb/cu in) [8] as defined by experimental X-ray crystallography. [a] 191 Ir and 193 Ir ...
17 hours ago · Vanadium is a chemical element; it has symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer ( passivation) somewhat stabilizes the free metal against further oxidation .
17 hours ago · Silicon dioxide (SiO 2) is a common fundamental constituent of glass. Fused quartz is a glass made from chemically pure silica. It has very low thermal expansion and excellent resistance to thermal shock, being able to survive immersion in water while red hot, resists high temperatures (1000–1500 °C) and chemical weathering, and is very hard.
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