Question

Molecular formula of sodium hydride is_ _ _
(A) $Na{{H}_{2}}$
(B) $N{{a}_{2}}{{H}_{2}}$
(C) $NaH$
(D) $N{{a}_{2}}H$

Answer 1

Hint: The term hydride is commonly named after binary compounds that hydrogen forms with other elements of the periodic table. The general formula being $M{{H}_{X}}$ , where M represents element and X the number of hydrogen atoms. This general formula was applicable for all elements except noble gases. Hydride is a negative ion of hydrogen${{H}^{-}}$, also called hydride ion. This negative charge of a hydride ion, the reason for reducing properties of hydrides.

Complete step by step solution:
From the general formula of hydrides, the general formula of sodium hydride is NaH and its molar mass is 24 g/mol. This sodium hydride belongs to the alkali metals group and its general configuration is $n{{s}^{1}}$ .
Sodium hydride is prepared by the direct reaction between sodium metal and hydrogen gas. This will soluble in molten Na.
$2Na+{{H}_{2}}\to 2NaH$
This alkali metal hydride is primarily used as a strong combustible base in organic synthesis. It is an ionic material with $N{{a}^{+}}$ and ${{H}^{-}}$ , is insoluble in organic solvents because of the insolubility of NaH with all reactions involving will occur at the surface of the solid.
Sodium hydride has octahedral crystal structure with each sodium ion surrounded by six hydride ions. The hydride ions give this molecule strong basic character.

The correct answer is Option C

Note: Depending upon the physical and chemical properties, these hydrides are divided into three following categories, ionic, metallic, and covalent hydrides. Due to the hydrogen bonding of these three hydrides, they have high boiling points and strong dipole-dipole attractions because of the high ionic character of the compounds.