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Acid strength is the tendency of an acid, symbolised by the chemical formula, to dissociate into a proton, +, and an anion, .The dissociation or ionization of a strong acid in solution is effectively complete, except in its most concentrated solutions.
On the other hand, if a chemical is a weak acid its conjugate base will not necessarily be strong. Consider that ethanoate, the conjugate base of ethanoic acid, has a base splitting constant (Kb) of about 5.6 × 10 −10, making it a weak base. In order for a species to have a strong conjugate base it has to be a very weak acid, like water.
In water, measurable pK a values range from about −2 for a strong acid to about 12 for a very weak acid (or strong base). A buffer solution of a desired pH can be prepared as a mixture of a weak acid and its conjugate base. In practice, the mixture can be created by dissolving the acid in water, and adding the requisite amount of strong acid ...
The simplest carboxylic acid, formic acid (HC(=O)−OH), is a moderately strong organic acid with a pK a of 3.7. We would expect vinylogous carboxylic acids to have similar acidity. Indeed, the vinylog of formic acid, 2-formyl-1-ethen-1-ol, HC(=O)−CH=CH−OH has a substantial Brønsted acidity, with an estimated pK a ~ 5–6.
For example, deprotonation of an alcohol forms the negatively charged alkoxide, which is a much stronger nucleophile. To determine whether or not a given base will be sufficient to deprotonate a specific acid, compare the conjugate base with the original base. A conjugate base is formed when the acid is deprotonated by the base.
A polar molecule has a net dipole as a result of the opposing charges (i.e. having partial positive and partial negative charges) from polar bonds arranged asymmetrically. Water (H 2 O) is an example of a polar molecule since it has a slight positive charge on one side and a slight negative charge on the other.
An organic acid is an organic compound with acidic properties. The most common organic acids are the carboxylic acids , whose acidity is associated with their carboxyl group –COOH. Sulfonic acids , containing the group –SO 2 OH, are relatively stronger acids.
A major factor in determining the reactivity of acyl derivatives is leaving group ability, which is related to acidity. Weak bases are better leaving groups than strong bases; a species with a strong conjugate acid (e.g. hydrochloric acid) will be a better leaving group than a species with a weak conjugate acid (e.g. acetic acid).