EAN of cobalt is 36 in `[Co(NH_3)_2 O_2 (en)Cl]`. Knowing that atomic number of `Co` is `27,O_2` is present as

Options

A. peroxide ion
B. dioxide ion
C. superoxide ion
D. oxide ion

Answer

A

Explanation

Peroxide = `O_(2)^(2-)`, dioxide = `2O^(2-)`, superoxide = `O_(2)^(-)`, oxide = `O^(2-)`
EAN = Z-Oxidation number `+2 xx` coordination number.
If `O_2` is present as `O_2^(-)` oxidation number of `Co = +2`.
EẠN `=27 - 2 + 2 xx 6 = 37`
If O is present as `O_2^(2-)`, oxidation number of `Co = +3`.
EAN`= 27-3 + 2 xx 6 = 36`