Answer:
D. nothing
Explanation:
Cobalt is one of the abundant in the Earth with a chemical configuration of
[Ar] 4s²3d⁷ and has oxidation states Co(ii) and Co(iii).It has two oxidation numbers +2 and +3.In nature Cobalt is found together with iron, nickel, silver and arsenic. It mostly resembles nickel and its significant application is in production of alloys such as Stellite.
