sil⋅i⋅ca
[sil-i-kuh] 
ɪ
| the dioxide form of silicon, SiO2, occurring esp. as quartz sand, flint, and agate: used usually in the form of its prepared white powder chiefly in the manufacture of glass, water glass, ceramics, and abrasives. |
Based on the Random House Dictionary, © Random House, Inc. 2009.
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| sil·i·ca (sĭl'ĭ-kə) n. A white or colorless crystalline compound, SiO2, occurring abundantly as quartz, sand, flint, agate, and many other minerals and used to manufacture a wide variety of materials, especially glass and concrete. [New Latin, from Latin silex, silic-, hard stone, flint.] |
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Silica
Sil"i*ca\, n. [NL., from L. silex, silics, a flint.] (Chem.) Silicon dioxide, SiO?. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder.Cite This Source
silica
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Main Entry: sil·i·ca
Pronunciation: 'sil-i-k&
Function: noun
: the dioxide of silicon SiO2 that is used as an ingredient ofsimethicone and that occurs naturally in crystalline, amorphous, and impure forms (as in quartz, opal, and sand respectively) called also silicon dioxide
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silica sil·i·ca (sĭl'ĭ-kə)
n.
A crystalline compound occurring abundantly as quartz, sand, and many other minerals and used to manufacture a variety of materials, especially glass and concrete.
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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| silica (sĭl'ĭ-kə) Pronunciation Key
A chemical compound that is the main constituent of most of the Earth's rocks. Silica occurs naturally in five crystalline forms (quartz, tridymite, cristobalite, coesite, and stishovite), in a cryptocrystalline form (chalcedony), and in an amorphous form (opal). It is also the main chemical compound in sand. Silica is used to make glass, concrete, and other materials. Also called silicon dioxide. Chemical formula: SiO2. |
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silica
compound of the two most abundant elements in the Earth's crust, silicon and oxygen, SiO2. The mass of the Earth's crust is 59 percent silica, the main constituent of more than 95 percent of the known rocks. Silica has three main crystalline varieties: quartz (by far the most abundant), tridymite, and cristobalite. Other varieties include coesite, keatite, and lechatelierite. Silica sand is used in buildings and roads in the form of portland cement, concrete, and mortar, as well as sandstone. Silica also is used in grinding and polishing glass and stone; in foundry molds; in the manufacture of glass, ceramics, silicon carbide, ferrosilicon, and silicones; as a refractory material; and as gemstones.
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