 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 . The existence of the hydride anion , suggested by Gilbert N. Lewis in 1916 for group 1 and 2 salt @-@ like hydrides , was demonstrated by Moers in 1920 by the electrolysis of molten lithium hydride ( <unk> ) , producing a stoichiometry quantity of hydrogen at the anode . For hydrides other than group 1 and 2 metals , the term is quite misleading , considering the low electronegativity of hydrogen . An exception in group 2 hydrides is <unk> 
