Question

The oxidation number of the central metal in a coordination entity is always a positive quantity.

(a) True

(b) False

This question was addressed to me in a job interview.

My doubt stems from Definitions topic in section Coordination Compounds of Chemistry – Class 12

Answer 1

Right choice is (b) False

The best I can explain: The oxidation number might not always be positive. It can also be 0 or a negative value. For example, the oxidation number of cobalt in K[Co(CO)4] is -1.