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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".
Hydride vapour-phase epitaxy (HVPE) is an epitaxial growth technique often employed to produce semiconductors such as GaN, GaAs, InP and their related compounds, in which hydrogen chloride is reacted at elevated temperature with the group-III metals to produce gaseous metal chlorides, which then react with ammonia to produce the group-III nitrides.
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).
A hydride compressor is a hydrogen compressor based on metal hydrides with absorption of hydrogen at low pressure, releasing heat, and desorption of hydrogen at high pressure, absorbing heat, by raising the temperature with an external heat source like a heated waterbed or electric coil.
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.
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.
Salt-like hydride selenides may be formed by heating selenium with a metal hydride in an oxygen-free capsule. For rare earth elements, this method works as long as selenium has enough oxidising power to convert a +2 oxidation state to a +3 state. So for europium and ytterbium it does not work as the monoselenide is more stable. [1]
The hydride ion is quite variable in size, ranging from 130 to 153 pm. [4] The hydride ion actually does not only have a −1 charge, but will have a charge dependent on its environment, so it is often written as H δ−. [4] In oxyhydrides, the hydride ion is much more compressible than the other atoms in compounds. [4]