Alkali metal hydrides are a class of chemical compounds composed of alkali metals (lithium, sodium, potassium, rubidium, caesium, and francium) in combination with hydrogen. They are typically represented as MHx, where M is the alkali metal and x varies depending on the specific compound. Lithium hydride (LiH), sodium hydride (NaH), and potassium hydride (KH) are the most commonly encountered forms. These compounds are highly reactive due to their strong reducing properties and can react violently with water, producing hydrogen gas and releasing significant heat. Alkali metal hydrides are used in various applications including chemical synthesis as reductants, hydrogen storage materials for fuel cells, and sources of hydrogen gas in laboratory settings. Due to their exothermic nature and corrosive behavior, they must be handled carefully under appropriate safety protocols.