Question

how to calculate oxidation number of-
1. Ni in Ni(CO) 4
2. Ba in BaSO4

Answer 1

1. oxidation no.of Ni =0
=x+4(0)=0
=x+0=0
=x=0
2.oxidation no.of Ba=8
=x+4(-2)=0
=x-8=0
=x=8