Question

Why is hydrogen kept in alkali metal group even though it shows properties of alkali metals like lithium and sodium and also the properties of halogens like fluorine and chlorine??

Answer 1

Although hydrogen shows properties of alkali metals like lithium and sodium and also the properties of halogens like fluorine and chlorine, it is placed in group 1 above alkali metals because its electronic configuration resembles the alkali metals. Group 1 consists of those elements which have one valence electron.Hydrogen has only one electron and the other elements of this group have one electron in their outermost shell.