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  2. Potassium oxide - Wikipedia

    en.wikipedia.org/wiki/Potassium_oxide

    K 2 O crystallises in the antifluorite structure. In this motif the positions of the anions and cations are reversed relative to their positions in CaF 2, with potassium ions coordinated to 4 oxide ions and oxide ions coordinated to 8 potassium. [6] [7] K 2 O is a basic oxide and reacts with water violently to produce the caustic potassium ...

  3. 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).

  4. Potassium superoxide - Wikipedia

    en.wikipedia.org/wiki/Potassium_superoxide

    Potassium superoxide is a source of superoxide, which is an oxidant and a nucleophile, depending on its reaction partner. [8]Upon contact with water, it undergoes disproportionation to potassium hydroxide, oxygen, and hydrogen peroxide:

  5. Structural formula - Wikipedia

    en.wikipedia.org/wiki/Structural_formula

    Lewis structures (or "Lewis dot structures") are flat graphical formulas that show atom connectivity and lone pair or unpaired electrons, but not three-dimensional structure. This notation is mostly used for small molecules. Each line represents the two electrons of a single bond. Two or three parallel lines between pairs of atoms represent ...

  6. Superoxide - Wikipedia

    en.wikipedia.org/wiki/Superoxide

    In chemistry, a superoxide is a compound that contains the superoxide ion, which has the chemical formula O − 2. [1] The systematic name of the anion is dioxide(1−).The reactive oxygen ion superoxide is particularly important as the product of the one-electron reduction of dioxygen O 2, which occurs widely in nature. [2]

  7. Natural bond orbital - Wikipedia

    en.wikipedia.org/wiki/Natural_bond_orbital

    In resonance structures, major and minor contributing structures may exist. For amides, for example, NBO calculations show that the structure with a carbonyl double bond is the dominant Lewis structure. However, in NBO calculations, "covalent-ionic resonance" is not needed due to the inclusion of bond-polarity effects in the resonance ...

  8. ECW model - Wikipedia

    en.wikipedia.org/wiki/ECW_Model

    For example, the shift of the phenol OH stretching frequency, Δχ, that occurs upon adduct formation has been analyzed using the following equation: Δ χ = Ε A ∗ E B + C A ∗ C B + W ∗ where asterisks on the E A and C A for phenol indicate that the acceptor is held constant and the frequency shift is measured as the base is varied.

  9. Linnett double-quartet theory - Wikipedia

    en.wikipedia.org/wiki/Linnett_Double-Quartet_Theory

    While Lewis’ model could explain the structures of many molecules, Lewis himself could not rationalise why electrons, negatively-charged particles which should repel, were able to form electron pairs in molecules or even why electrons can form a bond between atoms. [4] Lewis’ theory has been seminal in the understanding of the chemical bond.