0
Laury Roob ∙
family
Mendeleev
1s2-2s2-2p6-3s2-3p6-4s2-3d10-4p5
Family. Apex
1s22s22p63s23p5
Single bond.
It is phosphorous. It has valency of 3 and forms 3 bonds most easily among these.
This metal is francium.