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  2. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    Lewis structure of a water molecule. Lewis structures – also called Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDs) – are diagrams that show the bonding between atoms of a molecule, as well as the lone pairs of electrons that may exist in the molecule.

  3. 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.

  4. Binary compounds of silicon - Wikipedia

    en.wikipedia.org/wiki/Binary_compounds_of_silicon

    Experimental iron-silicon phase diagram. Binary compounds of silicon are binary chemical compounds containing silicon and one other chemical element. [1] Technically the term silicide is reserved for any compounds containing silicon bonded to a more electropositive element. Binary silicon compounds can be grouped into several classes.

  5. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    The equation is −ΔH = E A E B + C A C B + W. The W term represents a constant energy contribution for acid–base reaction such as the cleavage of a dimeric acid or base. The equation predicts reversal of acids and base strengths. The graphical presentations of the equation show that there is no single order of Lewis base strengths or Lewis ...

  6. Valence bond theory - Wikipedia

    en.wikipedia.org/wiki/Valence_bond_theory

    A valence bond structure resembles a Lewis structure, but when a molecule cannot be fully represented by a single Lewis structure, multiple valence bond structures are used. Each of these VB structures represents a specific Lewis structure. This combination of valence bond structures is the main point of resonance theory.

  7. Silicon dioxide - Wikipedia

    en.wikipedia.org/wiki/Silicon_dioxide

    The idealized equation involving a trisilicate and sulfuric acid is: Na 2 Si 3 O 7 + H 2 SO 4 3 SiO 2 + Na 2 SO 4 + H 2 O {\displaystyle {\ce {Na2Si3O7 + H2SO4 -> 3 SiO2 + Na2SO4 + H2O}}} Approximately one billion kilograms/year (1999) of silica were produced in this manner, mainly for use for polymer composites – tires and shoe soles.

  8. Silicate - Wikipedia

    en.wikipedia.org/wiki/Silicate

    Structure of the orthosilicate anion SiO 4− 4. A silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula [SiO (4-2x)− 4−x] n, where 0 ≤ x < 2. The family includes orthosilicate SiO 4− 4 (x = 0), metasilicate SiO 2− 3 (x = 1), and pyrosilicate Si 2 O 6− 7 (x = 0.5 ...

  9. Lewis acid catalysis - Wikipedia

    en.wikipedia.org/wiki/Lewis_Acid_Catalysis

    Two common modes of Lewis acid catalysis in reactions with polar mechanisms. In reactions with polar mechanisms, Lewis acid catalysis often involves binding of the catalyst to Lewis basic heteroatoms and withdrawing electron density, which in turn facilitates heterolytic bond cleavage (in the case of Friedel-Crafts reaction) or directly activates the substrate toward nucleophilic attack (in ...