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  2. Gutmann–Beckett method - Wikipedia

    en.wikipedia.org/wiki/Gutmann–Beckett_method

    Gutmann, a chemist renowned for his work on non-aqueous solvents, described an acceptor-number scale for solvent Lewis acidity [4] with two reference points relating to the 31 P NMR chemical shift of Et 3 PO in the weakly Lewis acidic solvent hexane (δ = 41.0 ppm, AN 0) and in the strongly Lewis acidic solvent SbCl 5 (δ = 86.1 ppm, AN 100).

  3. 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 ...

  4. Tetrakis (3,5-bis (trifluoromethyl)phenyl)borate - Wikipedia

    en.wikipedia.org/wiki/Tetrakis(3,5-bis(trifluoro...

    Extremely Lewis acidic metal centers can, however, cleave the carbon-boron bond in BARF. [12] NaBAr F 4 can be used in deprotection of acetal or ketal-protected carbonyl compounds. [13] [14] For example, deprotection of 2-phenyl-1,3-dioxolane to benzaldehyde can be achieved in water in five minutes at 30 °C. [15]

  5. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    Lewis structure of a water molecule. 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.

  6. Acetic acid - Wikipedia

    en.wikipedia.org/wiki/Acetic_acid

    acetyl chloride SOCl 2 acetic acid (i) Li[AlH 4], ether (ii) H 3 O + ethanol Two typical organic reactions of acetic acid Acetic acid undergoes the typical chemical reactions of a carboxylic acid. Upon treatment with a standard base, it converts to metal acetate and water. With strong bases (e.g., organolithium reagents), it can be doubly deprotonated to give LiCH 2 COOLi. Reduction of acetic ...

  7. 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 −

  8. Acidic oxide - Wikipedia

    en.wikipedia.org/wiki/Acidic_oxide

    An acidic oxide is an oxide that either produces an acidic solution upon addition to water, or acts as an acceptor of hydroxide ions effectively functioning as a Lewis acid. [1] Acidic oxides will typically have a low pK a and may be inorganic or organic. A commonly encountered acidic oxide, carbon dioxide produces an acidic solution (and the ...

  9. Brønsted–Lowry acid–base theory - Wikipedia

    en.wikipedia.org/wiki/Brønsted–Lowry_acid...

    A solution of B(OH) 3 is acidic because hydrogen ions are given off in this reaction. There is strong evidence that dilute aqueous solutions of ammonia contain minute amounts of the ammonium ion + + + and that, when dissolved in water, ammonia functions as a Lewis base. [18]