A [M(H2O)6]^2+ complex typically absorbs at around 600 nm. It is allowed to react with ammonia to fo — Coordination Compounds Chemistry Question

💡 Solution & Explanation

Step 1: Complexes of 4d and 5d metal ions, like Pd(II), always form square planar geometries with CN = 4 regardless of the ligand field strength, meaning [PdCl4]^2- and [Pd(CN)4]^2- are square planar. Step 2: For 3d^8 Ni(II), the strong-field CN^- ligand pairs up the electrons, yielding a dsp^2 hybridized square planar [Ni(CN)4]^2- complex. Step 3: In [NiCl4]^2-, the weak-field Cl^- ligand does not force pairing, leading to sp^3 hybridization and a tetrahedral shape. Thus, option (d) is correct.