Which elements in the nitrogen group are metals, nonmetals, or metalloids?
The differences among metals, non metals and metalloids are not so clear as one could think, though the metallic properties increase going from the top to the bottom of the group.
If nitrogen and phosphorus are securely non metals, you can find aresenic, antimony and bismuth both in the metals both in the non metals.
Arsenic forms many acids like
It forms salt as cation but also as anion
Also Bismuth may be