The oxidation number of Co in \([Co(en)_3]_2(SO_4)_3\) is:
Show Hint
- \(+3\)
- \(+2\)
- \(+4\)
- \(+6\)
The Correct Option is A
Solution and Explanation
Oxidation number of central metal ion is calculated by using the charges of ligands and counter ions. The ligand \(en\), ethylenediamine, is a neutral ligand. \[ en = 0 \] Sulphate ion has charge: \[ SO_4^{2-} \]
Step 1: Find total charge due to sulphate ions.
The compound is: \[ [Co(en)_3]_2(SO_4)_3 \] There are three sulphate ions. \[ 3 \times (-2)=-6 \] So the two complex cations must have total charge: \[ +6 \]
Step 2: Find charge on one complex ion.
There are two complex ions. \[ 2[Co(en)_3]^{x+}=+6 \] So charge on one complex ion is: \[ +3 \]
Step 3: Find oxidation state of Co.
Since \(en\) is neutral: \[ x+3(0)=+3 \] \[ x=+3 \] Hence: \[ \boxed{\text{(A) }+3} \]
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