Question

The structure of complex ion [Ni(CN)$_4$]$^{2-}$ is

• A. Linear
• B. Tetrahedral
• C. Square planar
• D. Octahedral

Hint:

For coordination complexes with a coordination number of 4, the most common geometry is tetrahedral, especially with ligands like CN$^-$.

Answer 1

The Correct Option is B

Step 1: Understand the complex ion structure.
The complex ion [Ni(CN)$_4$]$^{2-}$ involves nickel (Ni) at the center surrounded by four cyanide (CN$^-$) ligands. The geometry of such a complex is determined by the coordination number and the type of ligands involved.
Step 2: Determine the geometry.
Nickel (Ni) in this case has a coordination number of 4, which typically leads to a tetrahedral geometry. The CN$^-$ ligand is a linear ligand, and in the absence of other factors, a tetrahedral structure is favored.
Step 3: Apply to the options.
The correct geometry for [Ni(CN)$_4$]$^{2-}$ is tetrahedral, so the correct answer is (B).
Final Answer: \[ \boxed{\text{Tetrahedral}} \]