Answer:
See explanation
Step-by-step explanation:
In the periodic table, hydrogen is placed in group 1 for convenience. Hydrogen is not a metal, however, its common oxidation state is +1. It easily forms a univalent positive ion just like group 1 elements.
So, when hydrogen is combined with strongly electropositive metals such as sodium, lithium, etc, hydrogen accepts one electron and exhibits an oxidation state of -1 in those compounds.
Such compounds in which hydrogen is combined with strongly electropositive metals to give a binary compound is called a hydride.