Question

Consider the complex \( [Cu(NH_3)_4]^{2+} \). Which of the following statements is correct about this complex?

• A. The complex has a square planar geometry and the oxidation state of Cu is +2.
• B. The complex exhibits sp\(^3\) hybridization in the central metal ion.
• C. The ligand ammonia (NH\(_3\)) is a bidentate ligand.
• D. The complex shows a \(d^9\) electronic configuration for the metal ion.

Hint:

When determining the geometry of coordination complexes, the oxidation state of the central metal ion and the number of ligands play a crucial role in determining the hybridization and geometry.

Answer 1

The Correct Option is A

In the given complex, the copper ion has an oxidation state of +2. 

The ammonia (NH\(_3\)) acts as a monodentate ligand, meaning it can only form one bond with the metal. The geometry of this complex is square planar because copper(II) in this case typically exhibits square planar geometry when coordinated with four ligands, especially in the \(d^9\) configuration. 

- Statement A: The complex has a square planar geometry, and the oxidation state of Cu is +2, which is correct. 
- Statement B: The complex does not exhibit sp\(^3\) hybridization; rather, it exhibits \(dsp^2\) hybridization in square planar geometry. 
- Statement C: Ammonia (NH\(_3\)) is a monodentate ligand, not a bidentate ligand. 
- Statement D: The copper ion in this case has a \(d^9\) configuration, not a \(d^9\) electronic configuration, meaning it's incorrect to say the complex has a \(d^9\) configuration. 

Therefore, only statement A is correct.