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  2. Silicic acid - Wikipedia

    en.wikipedia.org/wiki/Silicic_acid

    No simple silicic acid has ever been identified, since these species are primarily of theoretical interest. Depending on the number of silicon atoms present, there are mono- and polysilicic (di-, tri-, tetrasilicic, etc.) acids. Well defined silicic acids have not been obtained in a form that has been characterized by X-ray crystallography.

  3. Orthosilicic acid - Wikipedia

    en.wikipedia.org/wiki/Orthosilicic_acid

    Orthosilicic acid (/ ˌ ɔːr θ ə s ɪ ˈ l ɪ s ɪ k /) is an inorganic compound with the formula Si(O H) 4. Although rarely observed, it is the key compound of silica and silicates and the precursor to other silicic acids [H 2x SiO x+2] n. Silicic acids play important roles in biomineralization and technology.

  4. Alkali–silica reaction - Wikipedia

    en.wikipedia.org/wiki/Alkali–silica_reaction

    Here, the silicic acid H 4 SiO 4, or Si(OH) 4, which is equivalent to SiO 2 · 2 H 2 O represents hydrous or amorphous silica for the sake of simplicity in aqueous chemistry. Indeed, the term silicic acid has traditionally been used as a synonym for silica, SiO 2. Strictly speaking, silica is the anhydride of orthosilicic acid, Si(OH) 4.

  5. Hydrated silica - Wikipedia

    en.wikipedia.org/wiki/Hydrated_silica

    When dissolved in water, it is usually known as silicic acid. It is found in nature as opal [2] (which has been mined as a gemstone for centuries), and in the cell walls of diatoms. It is also synthetically manufactured for use in toothpaste as an abrasive to assist in cleaning.

  6. Silica cycle - Wikipedia

    en.wikipedia.org/wiki/Silica_cycle

    [5] [6] It results in the generation of silicic acid in aqueous environments. Silicic acid, Si(OH) 4, is a hydrated form of silica found only as an unstable solution in water, yet it plays a central role in the silica cycle. [1] Silicifiers are organisms that use silicic acid to precipitate biogenic silica, SiO 2.

  7. Sodium silicate - Wikipedia

    en.wikipedia.org/wiki/Sodium_silicate

    Method 2 requires adding an ester (reaction product of an acid and an alcohol) to the mixture of sand and sodium silicate before it is placed into the molding box or core box. As the ester hydrolyzes from the water in the liquid sodium silicate, an acid is released which causes the liquid sodium silicate to gel.

  8. Biogenic silica - Wikipedia

    en.wikipedia.org/wiki/Biogenic_silica

    Silicate, or silicic acid (H 4 SiO 4), is an important nutrient in the ocean. Unlike the other major nutrients such as phosphate, nitrate, or ammonium, which are needed by almost all marine plankton, silicate is an essential chemical requirement for very specific biota, including diatoms, radiolaria, silicoflagellates, and siliceous sponges.

  9. Silica gel - Wikipedia

    en.wikipedia.org/wiki/Silica_gel

    Silica gel was in existence as early as the 1640s as a scientific curiosity. [5] It was used in World War I for the adsorption of vapors and gases in gas mask canisters.The synthetic route for producing silica gel was patented in 1918 by Walter A. Patrick, a chemistry professor at Johns Hopkins University.