Find the word definition

Crossword clues for silica

Longman Dictionary of Contemporary English
▪ For example, ethanol can be separated from a liquid mixture of ethanol and water by shaking the mixture with silica gel.
▪ The silica gel removes the water.
▪ High-temperature gas cleaning techniques remove the water and metal ions which are a natural constituent of silica glass, and attenuate light.
▪ Soda silica glasses are not very manageable, however.
▪ Because the silica in andesite makes it thick and pasty, andesite tends to trap large amounts of gas.
▪ Indeed as pure silica it is the insulating element in the technology of silicon microchips.
▪ Quartz is a crystalline form of silica.
▪ The most commonly used rocks are those composed of silica, quartz, granite, slate, and other similarly stable materials.
▪ This is not a result of sampling bias on our part, as all known sites of geothermal silica deposits were sampled.
▪ This model remains today the best For simple glasses, such as silica, and many of the new amorphous semiconductors.
The Collaborative International Dictionary

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.

Douglas Harper's Etymology Dictionary

"hard silicon dioxide," 1801, Modern Latin, from Latin silex (genitive silicis) "flint, pebble," on model of alumina, soda.


n. 1 silicon dioxide. 2 Any of the silica group of the silicate minerals.


n. a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechartelierite [syn: silicon oxide, silicon dioxide]

Silica (disambiguation)

Silica or silicon dioxide is a chemical compound.

Silica may also refer to:

  • Silica gel, a desiccant
  • Silica, Rožňava District, Slovakia
  • Silica, Kansas, United States
  • Silica, Minnesota, United States
  • Silica, West Virginia
  • Silica, Wisconsin, United States
  • USS Silica (IX-151), a boat
  • Silica, a character from the light novel and anime series Sword Art Online

Usage examples of "silica".

The two lots of silica are washed free from chlorides with hot water, dried on an air-bath, transferred to a platinum-crucible, ignited gently at first, at last strongly over the blast or in a muffle, cooled in a desiccator, and weighed.

The silica is washed by decantation two or three times with hydrochloric acid and hot water, before being thrown on to the filter.

The smoke thus produced reduces the red ferric oxide to blue-green ferrous oxide, or to metallic iron, which combines with the silica present to form a fusible ferrous silicate.

As the tide rose each piece was trundled on to the sloping beach, to be rolled and compressed until coated with a mosaic of white shell chips, angularities of silica and micaceous spangles, the finished article being cast aside as the tide receded.

Silicon fluoride is evolved, and, if a moistened glass rod is held in the tube, it becomes coated with a white deposit of silica, formed by the decomposition of the silicon fluoride by the water.

On holding a rod, moistened with a drop of water, over the escaping fumes, the white crust of silica formed on the drop of water shows its presence.

The residue may consist of unremoved silica, and oxides of tantalum, niobium, and, perhaps, chromium.

To prevent the photoactivity, modern pigmentary TiO2 is coated with silica.

Boussingault has shown that this is due to the formation of a silicide of platinum by means of the reduction of the silica of the carbon by the metal.

This may readily be done by adding terbium oxide with a little xerion to the silica.

Firstly, the silica contains a new catalyst, terbium oxide, one of the rare earths.

Ojo Caliente was constantly being reshaped and rebuilt, in places spongy, in other places cracked and hard and brittle, the stuff of geyserite: a hydrous form of silica, a variety of opal deposited in gray and white concretelike masses, porous, filamentous, and scaly.

The thinness of the silica layer is critical: it has to be just thick enough to block the photocatalysis, but not so thick that it degrades the optical properties of the TiO2.

After Silica, if the discharge continues too long and the wound refuses to heal owing to a torpidity of the tissues.

All clays contain more or less free silica in the form of sand, and usually a small percentage of undecomposed felspar.