Consider the following coordination complexes: (I) [ Fe ( H ₂ O )₆ ]²⁺ (II) [ Fe ( CN )₆ ]⁴⁻ (III) [ CoF ₆ ]³⁻ (IV) [ Co ( NH ₃ )₆ ]³⁺ Given below are three statements regarding their spin states and magnetic properties: Statement A : (I) and (III) are high-spin paramagnetic complexes. Statement B : (II) and (IV) are low-spin diamagnetic complexes. Statement C : The spin-only magnetic moment of (III) is greater than

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Determine the oxidation state and d -electron configuration for each central metal ion: (I) [ Fe ( H ₂ O )₆ ]²⁺ : Fe ²⁺ is 3d⁶ . H ₂ O is a weak field ligand, forming a high-spin complex ( t_ 2g ⁴ e_ g ² ). It has 4 unpaired electrons and is paramagnetic. (II) [ Fe ( CN )₆ ]⁴⁻ : Fe ²⁺ is 3d⁶ . CN ⁻ is a strong field ligand, forming a low-spin complex ( t_ 2g ⁶ e_ g ⁰ ). It has 0 unpaired electrons and is diamagnetic. (III) [ CoF ₆ ]³⁻ : Co ³⁺ is 3d⁶ . F ⁻ is a weak field ligand, forming a high-spin complex ( t_ 2g