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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".
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).
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 positively charged hydrogen ion (or proton) can readily combine with other particles and therefore is only seen isolated when it is in a gaseous state or a nearly particle-free space. [1] Due to its extremely high charge density of approximately 2×10 10 times that of a sodium ion, the bare hydrogen ion cannot exist freely in solution as it ...
The most common hydrogenating pair is an organosilane as the hydride source (e.g. triethylsilane), and a strong oxyacid as the proton source (e.g. trifluoroacetic acid or triflic acid). The hydride and proton source cannot combine to give H 2, which limits the hydricity and acidity of the H − and H + sources, respectively.
A sample of sodium hydride. Compounds of hydrogen are often called hydrides, a term that is used fairly loosely. The term "hydride" suggests that the H atom has acquired a negative or anionic character, denoted H −, and is used when hydrogen forms a compound with a more electropositive element.
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.
In ionic compounds, hydrogen can take the form of either a negatively charged anion, where it is known as hydride, or as a positively charged cation, H +. The cation, usually just a proton (symbol p), exhibits specific behavior in aqueous solutions and in ionic compounds involves screening of its electric charge by surrounding polar molecules ...