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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 organic solvents. The hydride reacts with water forming hydrogen and hydroxide salt. The dry solvent can then be distilled or vacuum transferred from the "solvent pot".
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.
Binary hydrogen compounds in group 1 are the ionic hydrides (also called saline hydrides) wherein hydrogen is bound electrostatically. Because hydrogen is located somewhat centrally in an electronegative sense, it is necessary for the counterion to be exceptionally electropositive for the hydride to possibly be accurately described as truly behaving ionic.
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
The loss of neutron moderation due to the chemical decomposition of the uranium hydride will consequently slow—and eventually halt—the reaction. When temperature returns to an acceptable level, the hydrogen will again combine with the uranium metal, forming uranium hydride, restoring moderation and the nuclear reaction will start again.
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 .
Aluminium hydride reduces acetals to half protected diols. [1] Acetal reduction using aluminium hydride. Aluminium hydride reduces epoxide to the corresponding alcohol: [1] Epoxide reduction using aluminium hydride. The allylic rearrangement reaction carried out using aluminium hydride is a S N 2 reaction, and it is not sterically demanding: [1]
The term hydride is probably most often used to describe compounds of hydrogen with other elements in which the hydrogen is in the formal −1 oxidation state. In most such compounds the bonding between the hydrogen and its nearest neighbor is covalent. An example of a hydride is the borohydride anion (BH − 4).