The oxidation number of Co in [Co(NH$_3$)$_5$(ONO)]SO$_4$ is :
Show Hint
- +3
- +2
- +4
- +6
The Correct Option is A
Solution and Explanation
Step 1: Identify ligand charges. \[ NH_3 \] is neutral. \[ ONO^- \] has charge \[ -1 \] Sulphate ion outside bracket: \[ SO_4^{2-} \] Therefore complex ion must have charge \[ +2 \]
Step 2: Let oxidation state of cobalt be x. \[ x+5(0)+(-1)=+2 \] \[ x-1=2 \] \[ x=3 \]
Step 3: Final answer. \[ \boxed{+3} \] Hence option (A) is correct.
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