For use in electronic devices, single crystals are grown by slowly withdrawing seed crystals from molten silicon. Almost pure silicon is obtained by the reduction of silicon tetrachloride or trichlorosilane. On a small scale, silicon can be obtained from the oxide by reduction with aluminum. Properties of the elementĮlemental silicon is produced commercially by the reduction of silica (SiO 2) with coke in an electric furnace, and the impure product is then refined. It is composed of the minerals feldspar, quartz, and one or more kinds of mica. Compared with the maximum of about 8.7 million electron volts for the nucleus of iron, almost twice as massive as that of silicon, this figure indicates the relative stability of the silicon nucleus. The energy binding the particles that form the nucleus of silicon is about 8.4 million electron volts (MeV) per nucleon ( proton or neutron). Silicon is believed to be a cosmic product of alpha-particle absorption, at a temperature of about 10 9 K, by the nuclei of carbon-12, oxygen-16, and neon-20. Only hydrogen, helium, oxygen, neon, nitrogen, and carbon exceed silicon in cosmic abundance. Estimates of the cosmic abundance of other elements often are cited in terms of the number of their atoms per 10 6 atoms of silicon. On a weight basis, the abundance of silicon in the crust of Earth is exceeded only by oxygen. Certainly, many of the naturally occurring compounds called silicates were used in various kinds of mortar for construction of dwellings by the earliest people. The manufacture of glass containing silica was carried out both by the Egyptians-at least as early as 1500 bce-and by the Phoenicians. In the form of rock crystal, however, silicon was familiar to the predynastic Egyptians, who used it for beads and small vases to the early Chinese and probably to many others of the ancients. Crystalline elemental silicon was not prepared until 1854, when it was obtained as a product of electrolysis. Impure silicon had already been obtained in 1811. The name silicon derives from the Latin silex or silicis, meaning “flint” or “hard stone.” Amorphous elemental silicon was first isolated and described as an element in 1824 by Jöns Jacob Berzelius, a Swedish chemist. Silicon makes up 27.7 percent of Earth’s crust it is the second most abundant element in the crust, being surpassed only by oxygen. Silicon (Si), a nonmetallic chemical element in the carbon family (Group 14 of the periodic table). SpaceNext50 Britannica presents SpaceNext50, From the race to the Moon to space stewardship, we explore a wide range of subjects that feed our curiosity about space!.Learn about the major environmental problems facing our planet and what can be done about them! Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century.Britannica Beyond We’ve created a new place where questions are at the center of learning.100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.COVID-19 Portal While this global health crisis continues to evolve, it can be useful to look to past pandemics to better understand how to respond today.Student Portal Britannica is the ultimate student resource for key school subjects like history, government, literature, and more.From tech to household and wellness products. ![]() This Time in History In these videos, find out what happened this month (or any month!) in history.#WTFact Videos In #WTFact Britannica shares some of the most bizarre facts we can find.Demystified Videos In Demystified, Britannica has all the answers to your burning questions.Britannica Explains In these videos, Britannica explains a variety of topics and answers frequently asked questions.Britannica Classics Check out these retro videos from Encyclopedia Britannica’s archives.
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