Which one of the following is wrongly matched?

Step-by-step solution

(a) In [ Cu ( NH ₃ )₄ ]²⁺, Cu is present as Cu ²⁺ Cu ²⁺=[ Ar ] 3 ~d ⁹ 4 ~s ⁰ ( NH ₃ . being a strong field ligand shifts one electron from 3 ~d orbital to 4 p orbital.) (b) In [ Ni ( CO )₄ ], CO is a neutral ligand. (c) In [ Fe ( CN )₆ ]³⁻ , Fe is present as Fe ³⁺ . aligned & Fe ³⁺=[ Ar ] 3 ~d ⁵ 4 ~s ⁰ & [ Fe ( CN )₆ ]³⁻=[ Ar ] aligned Thus, its hybridisation is d ² sp ³ not sp ³ ~d ² , ie, it is an inner orbital complex. (d) [ Co ( en )₃ ]³⁺ contains total 36 electrons, ie, follows EAN rule.