Elements with valency 1 are

In order to achieve an octet in the outermost shell, atoms would react. This is done by sharing, gaining or losing electrons. The number of electrons gained, lost or shared in the outermost shell determines the valency or combining capacity of the element. Both metals or non-metals can have valency 1 either by losing or gaining electrons. Metals usually form positive ions by losing an electron. Non-metals form negative ions by gaining an electron.