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Question #44852
The Question
Consider the following three coordination complexes synthesized at 298 K: I. \ce{K3[CoF6]} II. \ce{K2[PtCl4]} III. \ce{K3[RuF6]} Let , , and be the spin-only magnetic moments (in Bohr Magnetons) of complexes I, II, and III, respectively. Calculate the value of .
Options
- A.
27
- B.
59
- C.
67
- D.
3
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Mechanism_Trap
Don't get tricked by the process! Learn the mechanical traps used in competitive exam questions.
Concepts Behind This Question
d-orbital contraction|Magnetic Moment Quenching|Spin-Only Magnetic Moment
Why This Question Is Tricky
Common Mistakes
This question tests the 'd-orbital contraction' and its effect on Crystal Field Splitting Energy (CFSE).
Students often fall into the trap of applying the 3d-series spectrochemical series (where F- and Cl- are weak field ligands) to 4d and 5d metals.
The hidden variable is that the larger radial extension of 4d/5d orbitals leads to significantly greater ligand-metal overlap, increasing to the point where nearly all 4d/5d complexes are low-spin, regardless of the ligand.
Failing to account for this leads to incorrect high-spin assignments for Pt and Ru, resulting in the trap answers 59 or 67.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | D and F Block Elements - Class 12 |
| Concept | d-orbital contraction |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |