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प्रश्न
Read the passage carefully and answer the questions that follow.
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Crystal field splitting by various ligands Metal complexes show different colours due to d-d transitions. The complex absorbs light of specific wavelength to promote the electron from t2g to eg level. The colour of the complex is due to the transmitted light, which is complementary of the colour absorbed. The wave number of light absorbed by different complexes of Cr ion are given below:
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Answer the following questions:
(a) Out of ligands "A", "B", "C" and "D", which ligand causes maximum crystal field splitting? Why?
OR
Which of the two, “A” or “D” will be a weak field ligand? Why?
(b) Which of the complexes will be violet in colour? [CrA6]3- or [CrB6]3+ and why?
(Given: If 560 - 570 nm of light is absorbed, the colour of the complex observed is violet.)
(c) If the ligands attached to Cr3+ ion in the complexes given in the table above are water, cyanide ion, chloride ion, and ammonia (not in this order).
Identify the ligand, write the formula and IUPAC name of the following:
- [CrA6]3-
- [CrC6]3+
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उत्तर
(a) D Energy is directly proportional to the wave number. Maximum energy of light is required for an electron to jump from t2g to eg in case of [CrD6]3-.
OR
A, The splitting caused in least in this case as the energy required for electron to jump from t2g to eg., is minimum.
(b) [CrB6]3+, wavelength of light absorbed is `1/17830 = 560` nm for the complex while `1/13640` = 733 nm for [CrA6]3- complex.
(c)
- [CrCl6]3-, Hexachloridochromate (III) ion
- [Cr(NH3)6]3+, Hexaamminechromium (III) ion
\[\ce{A = Cl-, B = H2O, C = NH3, D = CN-}\]
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संबंधित प्रश्न
State the superiority of crystal field theory over valence bond theory.
Complete and balance the following reactions:
\[\ce{P4 + H2SO4 ->}\] ______ + ______ + ______
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Why are low spin tetrahedral complexes not formed?
Give the electronic configuration of the following complexes on the basis of Crystal Field Splitting theory.
\[\ce{[CoF6]^{3-}, [Fe(CN)6]^{4-} and [Cu(NH3)6]^{2+}}\].
Using crystal field theory, draw energy level diagram, write electronic configuration of the central metal atom/ion and determine the magnetic moment value in the following:
\[\ce{[CoF6]^{3-}, [Co(H2O)6]^{2+}, [Co(Cn)6]^{3-}}\]
What is the spectrochemical series?
Consider that d6 metal ion (M2+) forms a complex with aqua ligands and the spin only magnetic moment of the complex is 4.90 BM. The geometry and the crystal field stabilization energy of the complex are ______.
On the basis of crystal field theory, write the electronic configuration for the d5 ion with a weak ligand for which Δ0 < P.
On the basis of crystal field theory, write the electronic configuration for d4 with a strong field ligand for which Δ0 > P.
