Question

For the complex \( [Co(NH_3)_6]^{3+} \), what is the oxidation state of Co and the number of unpaired electrons?

• A. \( x = 2, y = 2 \)
• B. \( x = 3, y = 3 \)
• C. \( x = 3, y = 4 \)
• D. \( x = 4, y = 2 \)

Hint:

For coordination complexes, the oxidation state of the metal ion is determined by the charge on the complex and the nature of the ligands.

Answer 1

The Correct Option is B

Step 1: Understanding the Complex.
The complex is \( [Co(NH_3)_6]^{3+} \), and ammonia (NH\(_3\)) is a neutral ligand. The charge on the complex is +3, meaning the charge on the central metal ion \( Co^{3+} \) is +3.
Step 2: Determining Oxidation State and Unpaired Electrons.
For \( Co^{3+} \), the oxidation state of Co is +3. In a \( d^6 \) configuration for \( Co^{3+} \), the number of unpaired electrons is 3.
Step 3: Conclusion.
The correct answer is (B) \( x = 3, y = 3 \).