Question

Alkaline metals do not form dipositive ion.Give reasons

Answer 1

Alkali metals are members of Group I. They have only one electron in their outermost energy levels. To be stable they need to lose only that single electron in the outermost energy level thus forming monopositive ions. ... To be stable, they lose these two electrons to form dipositive ions.

Answer 2

Alkaline
metals have only one electron in valence shell, so they can loose one electron too form a mono positiveions only. while alkali earthmetals have two electrons in there valance shell so they loose two electrons toform a dipositive ion.