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  2. Carbocation - Wikipedia

    en.wikipedia.org/wiki/Carbocation

    By necessity of having five bonds on carbon but only four valence electron pairs available for bonding, they feature delocalized 3c-2e σ bonding and are thus regarded as type of non-classical carbocation. Like carbenium ions, carbonium ions are often invoked as intermediates in the upgrading of hydrocarbons in refineries.

  3. Oxocarbon anion - Wikipedia

    en.wikipedia.org/wiki/Oxocarbon_anion

    The electronic structure is described by two main theories which are used to show how the 4 electron pairs are distributed in a molecule that only has 3 C-O bonds. With valence bond theory the electronic structure of the carbonate ion is a resonance hybrid of 3 canonical forms. In each canonical form there are two single bonds one double bond.

  4. Ionic bonding - Wikipedia

    en.wikipedia.org/wiki/Ionic_bonding

    In the simplest case, the cation is a metal atom and the anion is a nonmetal atom, but these ions can be more complex, e.g. polyatomic ions like NH + 4 or SO 24. In simpler words, an ionic bond results from the transfer of electrons from a metal to a non-metal to obtain a full valence shell for both atoms.

  5. Carbon group - Wikipedia

    en.wikipedia.org/wiki/Carbon_group

    Double bonds are characteristic for carbon (alkenes, CO 2...); the same for π-systems in general. The tendency to lose electrons increases as the size of the atom increases, as it does with increasing atomic number. Carbon alone forms negative ions, in the form of carbide (C 4−) ions. Silicon and germanium, both metalloids, each can form +4 ...

  6. Carbenium ion - Wikipedia

    en.wikipedia.org/wiki/Carbenium_ion

    A carbocation may be stabilized by resonance by a carbon–carbon double bond or by the lone pair of a heteroatom adjacent to the ionized carbon. The allyl cation CH 2 =CH−CH + 2 and benzyl cation C 6 H 5 −CH + 2 are more stable than most other carbenium ions due to donation of electron density from π systems to the cationic center. [ 20 ]

  7. Ion association - Wikipedia

    en.wikipedia.org/wiki/Ion_association

    In chemistry, ion association is a chemical reaction whereby ions of opposite electric charge come together in solution to form a distinct chemical entity. [1] [2] Ion associates are classified, according to the number of ions that associate with each other, as ion pairs, ion triplets, etc. Ion pairs are also classified according to the nature of the interaction as contact, solvent-shared or ...

  8. Carbonium ion - Wikipedia

    en.wikipedia.org/wiki/Carbonium_ion

    All other C-C bond lengths are normal (ca. 1.5 Å). [1] In chemistry, a carbonium ion is a cation that has a pentacoordinated carbon atom. [2] They are a type of carbocation. In older literature, the name "carbonium ion" was used for what is today called carbenium. Carbonium ions charge is delocalized in three-center, two-electron bonds. The ...

  9. Isoelectronicity - Wikipedia

    en.wikipedia.org/wiki/Isoelectronicity

    Isoelectronicity is a phenomenon observed when two or more molecules have the same structure (positions and connectivities among atoms) and the same electronic configurations, but differ by what specific elements are at certain locations in the structure. For example, CO, NO +, and N 2 are isoelectronic, while CH 3 COCH 3 and CH 3 N = NCH 3 are ...