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  2. Lone pair - Wikipedia

    en.wikipedia.org/wiki/Lone_pair

    Thus, the number of electrons in lone pairs plus the number of electrons in bonds equals the number of valence electrons around an atom. Lone pair is a concept used in valence shell electron pair repulsion theory (VSEPR theory) which explains the shapes of molecules. They are also referred to in the chemistry of Lewis acids and bases. However ...

  3. Amine - Wikipedia

    en.wikipedia.org/wiki/Amine

    Amine. In chemistry, amines (/ ə ˈ m iː n, ˈ æ m iː n /, [1] [2] UK also / ˈ eɪ m iː n / [3]) are compounds and functional groups that contain a basic nitrogen atom with a lone pair.Formally, amines are derivatives of ammonia (NH 3 (in which the bond angle between the nitrogen and hydrogen is 170°), wherein one or more hydrogen atoms have been replaced by a substituent such as an ...

  4. Ammonia - Wikipedia

    en.wikipedia.org/wiki/Ammonia

    The molecule's polarity, and especially its ability to form hydrogen bonds, makes ammonia highly miscible with water. The lone pair makes ammonia a base, a proton acceptor. Ammonia is moderately basic; a 1.0 M aqueous solution has a pH of 11.6, and if a strong acid is added to such a solution until the solution is neutral (pH = 7), 99.4% of the ...

  5. Ammonium - Wikipedia

    en.wikipedia.org/wiki/Ammonium

    The lone electron pair on the nitrogen atom (N) in ammonia, represented as a line above the N, forms a coordinate bond with a proton (H +). After that, all four N−H bonds are equivalent, being polar covalent bonds. The ion has a tetrahedral structure and is isoelectronic with methane and the borohydride anion.

  6. Organic base - Wikipedia

    en.wikipedia.org/wiki/Organic_base

    An organic base is an organic compound which acts as a base. Organic bases are usually, but not always, proton acceptors. They usually contain nitrogen atoms, which can easily be protonated. For example, amines or nitrogen-containing heterocyclic compounds have a lone pair of electrons on the nitrogen atom and can thus act as proton acceptors. [1]

  7. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    typical soft bases: organophosphines, thioethers, carbon monoxide, iodide; For example, an amine will displace phosphine from the adduct with the acid BF 3. In the same way, bases could be classified. For example, bases donating a lone pair from an oxygen atom are harder than bases donating through a nitrogen atom.

  8. Coordinate covalent bond - Wikipedia

    en.wikipedia.org/wiki/Coordinate_covalent_bond

    An example of a dative covalent bond is provided by the interaction between a molecule of ammonia, a Lewis base with a lone pair of electrons on the nitrogen atom, and boron trifluoride, a Lewis acid by virtue of the boron atom having an incomplete octet of electrons. In forming the adduct, the boron atom attains an octet configuration.

  9. Base (chemistry) - Wikipedia

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

    G. N. Lewis realized that water, ammonia, and other bases can form a bond with a proton due to the unshared pair of electrons that the bases possess. [3] In the Lewis theory, a base is an electron pair donor which can share a pair of electrons with an electron acceptor which is described as a Lewis acid. [4]