Question

What is the electronic configuration for \( [Ni(CN)_4]^{2-} \)?

• A. \( [Ni(CN)_4]^{2-} \) has a \( d^8 \) configuration.
• B. \( [Ni(CN)_4]^{2-} \) has a \( d^{sp^2} \) configuration.
• C. \( [Ni(CN)_4]^{2-} \) has a \( d^6 \) configuration.
• D. \( [Ni(CN)_4]^{2-} \) has a \( d^4 \) configuration.

Hint:

For coordination complexes, the hybridization depends on the nature of the ligands. Strong field ligands like cyanide cause low-spin configurations and \( d^{sp^2} \) hybridization.

Answer 1

The Correct Option is B

Step 1: Understanding the Complex.
In the complex \( [Ni(CN)_4]^{2-} \), the oxidation state of Ni is +2. The electronic configuration of Ni is \( [Ar] 3d^8 4s^2 \), and for \( Ni^{2+} \), the configuration becomes \( [Ar] 3d^8 \).
Step 2: Determining the Hybridization.
The cyanide ions (CN\(^-\)) are strong field ligands, leading to low-spin configuration and \( d^{sp^2} \) hybridization.
Step 3: Conclusion.
The correct answer is (B) \( [Ni(CN)_4]^{2- \) has a \( d^{sp^2} \) configuration.}