[Fe(H2O)6]^2+ and [Fe(CN)6]^4- differ in : — Coordination Compounds Chemistry Question

💡 Solution & Explanation

Step 1: Both complexes have the same octahedral geometry and are complexes of Fe^2+ with 6 d-electrons. Step 2: [Fe(H2O)6]^2+ uses weak-field H2O, giving a high-spin state with 4 unpaired electrons and a pale green colour. [Fe(CN)6]^4- uses strong-field CN^-, giving a low-spin state with 0 unpaired electrons (diamagnetic) and a yellow colour. Step 3: Thus, they differ in their magnetic moments and colours, making option (c) the correct choice.