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[15] In Lewis theory an acid, A, and a base, B, form an adduct, AB, where the electron pair forms a dative covalent bond between A and B. This is shown when the adduct H 3 N−BF 3 forms from ammonia and boron trifluoride, a reaction that cannot occur in water because boron trifluoride hydrolizes in water. [16]
For the two base parameters, E B for CH 3 C(O)N(CH 3) 2 was set at 2.35 and C B for (C 2 H 5) 2 S, diethyl sulfide, was set at 3.92. Fixing the parameters in this way imposed the covalent-electrostatic model on the data set by fixing the E A E B and C A C B products of the DMA and (C 2 H 5 ) 2 S adducts with iodine, and these four values ...
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.
One use of conjugate acids and bases lies in buffering systems, which include a buffer solution. In a buffer, a weak acid and its conjugate base (in the form of a salt), or a weak base and its conjugate acid, are used in order to limit the pH change during a titration process.
Pauling's second rule is that the value of the first pK a for acids of the formula XO m (OH) n depends primarily on the number of oxo groups m, and is approximately independent of the number of hydroxy groups n, and also of the central atom X. Approximate values of pK a are 8 for m = 0, 2 for m = 1, −3 for m = 2 and < −10 for m = 3. [28]
As an acid, losing a proton: HCO − 3 + OH − ⇌ CO 2− 3 + H 2 O As a base, accepting a proton: HCO − 3 + H + ⇌ H 2 CO 3. Note: in dilute aqueous solution the formation of the hydronium ion, H 3 O + (aq), is effectively complete, so that hydration of the proton can be ignored in relation to the equilibria.
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.
Acidimetry is the specialized analytical use of acid-base titration to determine the concentration of a basic (alkaline) substance using standard acid. This can be used for weak bases and strong bases. [8] An example of an acidimetric titration involving a strong base is as follows: Ba(OH) 2 + 2 H + → Ba 2+ + 2 H 2 O