enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Germanium dioxide - Wikipedia

    en.wikipedia.org/wiki/Germanium_dioxide

    The hexagonal (d = 4.29 g/cm 3) form of germanium dioxide is more soluble than the rutile (d = 6.27 g/cm 3) form and dissolves to form germanic acid, H 4 GeO 4, or Ge(OH) 4. [6] GeO 2 is only slightly soluble in acid but dissolves more readily in alkali to give germanates. [6]

  3. Silicon dioxide - Wikipedia

    en.wikipedia.org/wiki/Silicon_dioxide

    Silicon dioxide is a relatively inert material (hence its widespread occurrence as a mineral). Silica is often used as inert containers for chemical reactions. At high temperatures, it is converted to silicon by reduction with carbon. Fluorine reacts with silicon dioxide to form SiF 4 and O 2 whereas the other halogen gases (Cl 2, Br 2, I 2 ...

  4. Germanium compounds - Wikipedia

    en.wikipedia.org/wiki/Germanium_compounds

    Two oxides of germanium are known: germanium dioxide (GeO 2, germania) and germanium monoxide, (GeO). [4] The dioxide, GeO 2 can be obtained by roasting germanium disulfide (GeS 2) or by allowing elemental germanium to slowly oxidze in air, [5] and is a white powder that is only slightly soluble in water but reacts with alkalis to form germanates. [4]

  5. Silicic acid - Wikipedia

    en.wikipedia.org/wiki/Silicic_acid

    In chemistry, a silicic acid (/ s ɪ ˈ l ɪ s ɪ k /) is any chemical compound containing the element silicon attached to oxide (=O) and hydroxyl (−OH) groups, with the general formula [H 2x SiO x+2] n or, equivalently, [SiO x (OH) 4−2x] n. [1] [2] Orthosilicic acid is a representative example.

  6. Geopolymer - Wikipedia

    en.wikipedia.org/wiki/Geopolymer

    The fundamental unit within a geopolymer structure is a tetrahedral complex consisting of silicon or aluminum coordinated through covalent bonds to four oxygens. The geopolymer framework results from the cross-linking between these tetrahedra, which leads to a 3-dimensional aluminosilicate network, where the negative charge associated with tetrahedral aluminium is balanced by a small cationic ...

  7. Acidic oxide - Wikipedia

    en.wikipedia.org/wiki/Acidic_oxide

    Carbonic acid is an illustrative example of the Lewis acidity of an acidic oxide. CO 2 + 2OH − ⇌ HCO 3 − + OH − ⇌ CO 3 2− + H 2 O. This property is a key reason for keeping alkali chemicals well sealed from the atmosphere, as long-term exposure to carbon dioxide in the air can degrade the material.

  8. Silicon–oxygen bond - Wikipedia

    en.wikipedia.org/wiki/Silicon–oxygen_bond

    A silicon–oxygen bond (Si−O bond) is a chemical bond between silicon and oxygen atoms that can be found in many inorganic and organic compounds. [1] In a silicon–oxygen bond, electrons are shared unequally between the two atoms, with oxygen taking the larger share due to its greater electronegativity.

  9. Precipitated silica - Wikipedia

    en.wikipedia.org/wiki/Precipitated_silica

    Precipitated silica is an amorphous form of silica (silicon dioxide, SiO 2); it is a white, powdery material. Precipitated silica is produced by precipitation from a solution containing silicate salts. The three main classes of amorphous silica are pyrogenic silica, precipitated silica and silica gel.