Question

For the complex ion [Fe(CN)₆]³⁻, state the oxidation number of the central metal atom.

Answer 1

Let the oxidation state of Fe be x:

x + 6(−1) = −3

x − 6 = −3

x = −3 + 6

x =  +3

The oxidation number of the central metal atom, iron (Fe), in the complex ion [Fe(CN)₆]³⁻ is +3.