Oxidation number is the charge assigned to an atom of a molecule or ion according to some arbitry rules .In neutral molecules , the sum of the oxidation numbers of all the atoms present is zero while in a simple or complex ion it is equal to the net charge on ion. In some cases the oxidation number may be even fractional. Athough sometimes a particular elemenet may have same valency and oxidation state but these are based upon different concepts.The number of oxidation states available for a particular elements are normally more than the valencies
A brown complex has the formula:
`[Fe(H_(2))(O)_(5)NO]SO_(4)` the oxidation number of iron is:

Options

A. `+1`
B. `+2`
C. `+3`
D. 0

Answer

A

Explanation

`[Fe(H_(2)O)_(5)NO]SO_(4)`
`x+0+1=+2`
`x=2-1=+1`