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  2. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    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. [1][2][3] A Lewis structure can be drawn for any covalently bonded ...

  3. Resonance (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Resonance_(chemistry)

    Contributing structures of the carbonate ion. In chemistry, resonance, also called mesomerism, is a way of describing bonding in certain molecules or polyatomic ions by the combination of several contributing structures (or forms, [1] also variously known as resonance structures or canonical structures) into a resonance hybrid (or hybrid structure) in valence bond theory.

  4. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    The most common Lewis bases are anions. The strength of Lewis basicity correlates with the pK a of the parent acid: acids with high pK a 's give good Lewis bases. As usual, a weaker acid has a stronger conjugate base. Examples of Lewis bases based on the general definition of electron pair donor include: simple anions, such as H − and F −

  5. Chemical bond - Wikipedia

    en.wikipedia.org/wiki/Chemical_bond

    A chemical bond is the association of atoms or ions to form molecules, crystals, and other structures. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds, or some combination of these effects.

  6. Radical (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Radical_(chemistry)

    Lewis dot structure of a Hydroxide ion compared to a hydroxyl radical. In chemistry, a radical, also known as a free radical, is an atom, molecule, or ion that has at least one unpaired valence electron. [1][2] With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spontaneously dimerize.

  7. Lewis number - Wikipedia

    en.wikipedia.org/wiki/Lewis_number

    Lewis number. In fluid dynamics and thermodynamics, the Lewis number (denoted Le) is a dimensionless number defined as the ratio of thermal diffusivity to mass diffusivity. It is used to characterize fluid flows where there is simultaneous heat and mass transfer. The Lewis number puts the thickness of the thermal boundary layer in relation to ...

  8. History of chemistry - Wikipedia

    en.wikipedia.org/wiki/History_of_chemistry

    Lewis's model equated the classical chemical bond with the sharing of a pair of electrons between the two bonded atoms. Lewis introduced the "electron dot diagrams" in this paper to symbolize the electronic structures of atoms and molecules. Now known as Lewis structures, they are discussed in virtually every introductory chemistry book.

  9. Lone pair - Wikipedia

    en.wikipedia.org/wiki/Lone_pair

    Lone pair. In chemistry, a lone pair refers to a pair of valence electrons that are not shared with another atom in a covalent bond [1] and is sometimes called an unshared pair or non-bonding pair. Lone pairs are found in the outermost electron shell of atoms. They can be identified by using a Lewis structure.