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प्रश्न
What is the spectrochemical series?
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उत्तर
Crystal field splitting, Δo depends on the field produced by the charge present on the ligand and the metal ion. Some ligands can produce strong fields and in such a case the splitting is more, while others produce weak fields due to which the splitting of d-orbitals is less. Generally, ligands can be arranged in a series in the order of their increasing field strength as follows:
\[\ce{I^- < Br^- < SCN^- < Cl^- < S^2- < F^- < OH^- < C2O^{2-}_4 < H2O < NCS^- < EDTA^{4-} < NH3 < en < CN^- < CO}\]
This type of series is called a spectrochemical series. It is determined by experimental facts based on the absorption of light by complexes formed with different ligands.
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संबंधित प्रश्न
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\[\ce{P4 + H2SO4 ->}\] ______ + ______ + ______
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Match the complex ions given in Column I with the hybridisation and number of unpaired electrons given in Column II and assign the correct code:
| Column I (Complex ion) | Column II (Hybridisation, number of unpaired electrons) |
| A. \[\ce{[Cr(H2O)6]^{3+}}\] | 1. dsp2, 1 |
| B. \[\ce{[Co(CN)4]^{2-}}\] | 2. sp3d2, 5 |
| C. \[\ce{[Ni(NH3)6]^{2+}}\] | 3. d2sp3, 3 |
| D. \[\ce{[MnF6]^{4-}}\] | 4. sp3, 4 |
| 5. sp3d2, 2 |
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