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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. 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 −

  4. Frustrated Lewis pair - Wikipedia

    en.wikipedia.org/wiki/Frustrated_Lewis_pair

    Non-nucleophilic. Weak. v. t. e. A frustrated Lewis pair (FLP) is a compound or mixture containing a Lewis acid and a Lewis base that, because of steric hindrance, cannot combine to form a classical adduct. [1] Many kinds of FLPs have been devised, and many simple substrates exhibit activation. [2][3] The discovery that some FLPs split H 2[4 ...

  5. HSAB theory - Wikipedia

    en.wikipedia.org/wiki/HSAB_theory

    HSAB theory. HSAB is an acronym for "hard and soft (Lewis) acids and bases ". HSAB is widely used in chemistry for explaining the stability of compounds, reaction mechanisms and pathways. It assigns the terms 'hard' or 'soft', and 'acid' or 'base' to chemical species. 'Hard' applies to species which are small, have high charge states (the ...

  6. VSEPR theory - Wikipedia

    en.wikipedia.org/wiki/VSEPR_theory

    The bond angle for water is 104.5°. Valence shell electron pair repulsion (VSEPR) theory (/ ˈvɛspər, vəˈsɛpər / VESP-ər, [1]: 410 və-SEP-ər[2]) is a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms. [3] It is also named the Gillespie-Nyholm ...

  7. Acid–base reaction - Wikipedia

    en.wikipedia.org/wiki/Acid–base_reaction

    In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base.It can be used to determine pH via titration.Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.

  8. Lewis acid catalysis - Wikipedia

    en.wikipedia.org/wiki/Lewis_Acid_Catalysis

    Lewis acid catalysis. In Lewis acid catalysis of organic reactions, a metal-based Lewis acid acts as an electron pair acceptor to increase the reactivity of a substrate. Common Lewis acid catalysts are based on main group metals such as aluminum, boron, silicon, and tin, as well as many early (titanium, zirconium) and late (iron, copper, zinc ...

  9. Single bond - Wikipedia

    en.wikipedia.org/wiki/Single_bond

    In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. [1] Therefore, a single bond is a type of covalent bond. When shared, each of the two electrons involved is no longer in the sole possession of the orbital in which it originated.