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The hydride adds to an electrophilic center, typically unsaturated carbon. Hydrides such as sodium hydride and potassium hydride are used as strong bases in organic synthesis. The hydride reacts with the weak Bronsted acid releasing H 2. Hydrides such as calcium hydride are used as desiccants, i.e. drying agents, to remove trace water from ...
A metal hydride can be a thermodynamically a weak acid and a weak H − donor; it could also be strong in one category but not the other or strong in both. The H − strength of a hydride also known as its hydride donor ability or hydricity corresponds to the hydride's Lewis base strength. Not all hydrides are powerful Lewis bases.
Potassium hydride is produced by direct combination of the metal and hydrogen at temperatures between 200 and 350 °C: 2 K + H 2 → 2 KH. This reaction was discovered by Humphry Davy soon after his 1807 discovery of potassium, when he noted that the metal would vaporize in a current of hydrogen when heated just below its boiling point. [4]: p.25
With anhydrous organic acids, phenols and acid anhydrides, LiH reacts slowly, producing hydrogen gas and the lithium salt of the acid. With water-containing acids, LiH reacts faster than with water. [3]: 8 Many reactions of LiH with oxygen-containing species yield LiOH, which in turn irreversibly reacts with LiH at temperatures above 300 °C ...
In solution—typically in ethereal solvents such tetrahydrofuran or diethyl ether—aluminium hydride forms complexes with Lewis bases, and reacts selectively with particular organic functional groups (e.g., with carboxylic acids and esters over organic halides and nitro groups), and although it is not a reagent of choice, it can react with ...
According to the original formulation of Lewis, when a neutral base forms a bond with a neutral acid, a condition of electric stress occurs. [7] The acid and the base share the electron pair that formerly belonged to the base. [7] As a result, a high dipole moment is created, which can only be decreased to zero by rearranging the molecules. [7]
Sodium hydride is the chemical compound with the empirical formula Na H.This alkali metal hydride is primarily used as a strong yet combustible base in organic synthesis.NaH is a saline (salt-like) hydride, composed of Na + and H − ions, in contrast to molecular hydrides such as borane, silane, germane, ammonia, and methane.
Another possibility is the molecular autoionization reaction between two water molecules, in which one water molecule acts as an acid and another as a base. H 2 O + H 2 O ⇌ H 3 O + + HO −. The bicarbonate ion, HCO − 3, is amphoteric as it can act as either an acid or a base: As an acid, losing a proton: HCO − 3 + OH − ⇌ CO 2− 3 ...