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  2. Silicon dioxide - Wikipedia

    en.wikipedia.org/wiki/Silicon_dioxide

    Fluorine reacts with silicon dioxide to form SiF 4 and O 2 whereas the other halogen gases (Cl 2, Br 2, I 2) are unreactive. [15] Most forms of silicon dioxide are attacked ("etched") by hydrofluoric acid (HF) to produce hexafluorosilicic acid: [12] SiO 2 + 6 HF → H 2 SiF 6 + 2 H 2 O. Stishovite does not react to HF to any significant degree ...

  3. Silicon compounds - Wikipedia

    en.wikipedia.org/wiki/Silicon_compounds

    The silicides of the group 1 and 2 metals usually are more reactive than the transition metal silicides. The latter usually do not react with aqueous reagents, except for hydrofluoric acid; however, they do react with much more aggressive reagents such as liquid potassium hydroxide, or gaseous fluorine or chlorine when red-hot.

  4. Quartz - Wikipedia

    en.wikipedia.org/wiki/Quartz

    Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. [9] Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation ...

  5. Serpentinization - Wikipedia

    en.wikipedia.org/wiki/Serpentinization

    Serpentinization is a hydration and metamorphic transformation of ferromagnesian minerals, such as olivine and pyroxene, in mafic and ultramafic rock to produce serpentinite. [1] Minerals formed by serpentinization include the serpentine group minerals ( antigorite , lizardite , chrysotile ), brucite , talc , Ni-Fe alloys, and magnetite .

  6. Mineral alteration - Wikipedia

    en.wikipedia.org/wiki/Mineral_alteration

    Mineral alteration refers to the various natural processes that alter a mineral's chemical composition or crystallography. [1]Mineral alteration is essentially governed by the laws of thermodynamics related to energy conservation, relevant to environmental conditions, often in presence of catalysts, the most common and influential being water (H 2 O).

  7. Fused quartz - Wikipedia

    en.wikipedia.org/wiki/Fused_quartz

    Fused quartz has nearly ideal properties for fabricating first surface mirrors such as those used in telescopes. The material behaves in a predictable way and allows the optical fabricator to put a very smooth polish onto the surface and produce the desired figure with fewer testing iterations.

  8. Carbonate–silicate cycle - Wikipedia

    en.wikipedia.org/wiki/Carbonate–silicate_cycle

    The inorganic cycle begins with the production of carbonic acid (H 2 CO 3) from rainwater and gaseous carbon dioxide. [6] Due to this process, normal rain has a pH of around 5.6. [7] Carbonic acid is a weak acid, but over long timescales, it can dissolve silicate rocks

  9. Solid acid - Wikipedia

    en.wikipedia.org/wiki/Solid_acid

    Crystalline benzoic acid shown here is a solid and an acid, but, in the context of this article, it is not a "solid acid", which are polymeric materials and typically stronger acids. Examples of inorganic solid acids include silico-aluminates ( zeolites , alumina , silico-aluminophosphate), and sulfated zirconia .