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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

    [1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [ 4 ] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.

  4. 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 ...

  5. Ball-and-stick model - Wikipedia

    en.wikipedia.org/wiki/Ball-and-stick_model

    [2] In a ball-and-stick model, the radius of the spheres is usually much smaller than the rod lengths, in order to provide a clearer view of the atoms and bonds throughout the model. As a consequence, the model does not provide a clear insight about the space occupied by the model.

  6. 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 ...

  7. Potassium superoxide - Wikipedia

    en.wikipedia.org/wiki/Potassium_superoxide

    4 KO 2 + 4 CO 2 + 2 H 2 O → 4 KHCO 3 + 3 O 2. Theoretically, 1 kg of KO 2 absorbs 0.310 kg of CO 2 while releasing 0.338 kg of O 2. One mole of KO 2 absorbs 0.5 moles of CO 2 and releases 0.75 moles of oxygen. Potassium superoxide finds only niche uses as a laboratory reagent. Because it reacts with water, KO 2 is often studied in

  8. Skeletal formula - Wikipedia

    en.wikipedia.org/wiki/Skeletal_formula

    The skeletal formula of the antidepressant drug escitalopram, featuring skeletal representations of heteroatoms, a triple bond, phenyl groups and stereochemistry. The skeletal formula, line-angle formula, bond-line formula or shorthand formula of an organic compound is a type of molecular structural formula that serves as a shorthand representation of a molecule's bonding and some details of ...

  9. ECW model - Wikipedia

    en.wikipedia.org/wiki/ECW_Model

    The W term represents a constant energy for cleavage of a dimeric acid or base. For example, the enthalpy of cleavage the [Rh(CO) 2 Cl] 2 by base B involves two steps. The first step is cleavage of the dimer, which is W: ⁠ 1 / 2 ⁠ [Rh(CO) 2 Cl] 2 → Rh(CO) 2 Cl W = −10.39 kcal/mol. The second step is the binding of B to RhCl(CO) 2 monomer.