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  2. Spectroscopic notation - Wikipedia

    en.wikipedia.org/wiki/Spectroscopic_notation

    This notation is used to specify electron configurations and to create the term symbol for the electron states in a multi-electron atom. When writing a term symbol, the above scheme for a single electron's orbital quantum number is applied to the total orbital angular momentum associated to an electron state. [4]

  3. Tin(II) chloride - Wikipedia

    en.wikipedia.org/wiki/Tin(II)_chloride

    Tin(II) chloride also behaves as a Lewis acid, forming complexes with ligands such as chloride ion, for example: SnCl 2 (aq) + CsCl (aq) → CsSnCl 3 (aq) Most of these complexes are pyramidal, and since complexes such as SnCl − 3 have a full octet, there is little tendency to add more than one ligand.

  4. Lewis number - Wikipedia

    en.wikipedia.org/wiki/Lewis_number

    It is named after Warren K. Lewis (1882–1975), [6] [7] who was the first head of the Chemical Engineering Department at MIT. Some workers in the field of combustion assume (incorrectly) that the Lewis number was named for Bernard Lewis (1899–1993), who for many years was a major figure in the field of combustion research. [citation needed]

  5. Hughes–Ingold symbol - Wikipedia

    en.wikipedia.org/wiki/Hughes–Ingold_symbol

    A Hughes–Ingold symbol describes various details of the reaction mechanism and overall result of a chemical reaction. [1] For example, an S N 2 reaction is a substitution reaction ("S") by a nucleophilic process ("N") that is bimolecular ("2" molecular entities involved) in its rate-determining step .

  6. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    Expressing resonance when drawing Lewis structures may be done either by drawing each of the possible resonance forms and placing double-headed arrows between them or by using dashed lines to represent the partial bonds (although the latter is a good representation of the resonance hybrid which is not, formally speaking, a Lewis structure).

  7. 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 ...

  8. Tin(II) oxide - Wikipedia

    en.wikipedia.org/wiki/Tin(II)_oxide

    SnO may be prepared as a pure substance in the laboratory, by controlled heating of tin(II) oxalate (stannous oxalate) in the absence of air or under a CO 2 atmosphere. This method is also applied to the production of ferrous oxide and manganous oxide. [5] [6] SnC 2 O 4 ·2H 2 O → SnO + CO 2 + CO + 2 H 2 O

  9. Donor number - Wikipedia

    en.wikipedia.org/wiki/Donor_number

    In chemistry a donor number (DN) is a quantitative measure of Lewis basicity.A donor number is defined as the negative enthalpy value for the 1:1 adduct formation between a Lewis base and the standard Lewis acid SbCl 5 (antimony pentachloride), in dilute solution in the noncoordinating solvent 1,2-dichloroethane with a zero DN.