A hydride is a compound formed by a hydrogen and any other element. When the chemical compound is composed of a hydrogen and a metal , It's about a metal hydride . However, if hydrogen is combined with an element that is not a metal, it is named as non metallic hydride .
Metal hydrides are named throughout the term "Hydride" followed by the preposition "from" and the denomination of metal : calcium hydride , lithium hydride , etc. As for its formula, the symbol of the metallic element is first written. Calcium hydride, in this sense, has the formula CaH2 (AC is calcium ), Meanwhile he lithium hydride take the formula LiH (the symbol of lithium is Li ).
The chemical compound called lithium hydride it is a crystalline solid without colour , although commercial samples exhibit a grayish hue. Another way to define it is as an inorganic salt composed of hydride anions H- and lithium Li + cations. Something that it shares with the rest of saline hydrides is a high melting point, in this case 689 degrees Celsius. Since its ions are extremely light, its molecular mass close to 8 and a density of 780 kilograms per cubic meter, the smallest of any compound in this class.
Lithium hydride has several applications, such as the following:
* In the process that is carried out to synthesize lithium aluminum hydride, it acts as precursor ;
* in the generation and storage of hydrogen;
* in nuclear reactors, it is used to shield and cool;
* as part of pottery making;
* It is a reducing agent.
It is necessary to point out that lithium is the lightest of cations , within the group of hydrides. In addition, lithium hydride has the highest hydrogen content of all hydrides: compared to sodium, we can say that it exceeds three times. With regard to the storage of hydrogen, one of the most frequent uses of this compound, its tendency to decomposition usually negatively affects its potential.
On the other hand we have the sodium hydride , a chemical compound whose formula is Nah . In the construction of organic molecules through chemical reactions (a process known as Organic synthesis), this hydride is used as a strong base.
One of the main differences between the hydride of sodium and other nonmetals, such as methane, ammonia and borane, it is ionizable, soluble in molten sodium and insoluble in organic solvents. Because of its insolubility, the reactions of this hydride occur on the surface. To generate it, a reaction of liquid sodium and hydrogen must be carried out. With respect to its density, it exceeds sodium by 40 percent.
Importantly, metal hydrides are the only ones compounds in which hydrogen presents the oxidation number -1 .
In non-metallic hydrides, however, the number of oxidation of hydrogen is 1 (positive; that is, +1 ). In these cases, the nonmetal is presented with its lowest valence number and, at room temperature, it is in a gaseous state.
To name a non-metallic hydride, the termination must be added -aurochs to root of the nonmetal and then specify "Of hydrogen": hydrogen chloride (chlorine + hydrogen), hydrogen fluoride (fluorine + hydrogen).
It should be noted that, depending on the kind of element with which it is combined, the hydrogen in the hydrides can form ionic or covalent bonds. By associating with the other element directly, the molecule the new compound dissociates and forms.