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प्रश्न
[Ni(H2O)6]2+ (aq) is green in colour whereas [Ni(H2O)4 (en)]2+ (aq)is blue in colour, give reason in support of your answer.
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उत्तर
The colour of coordination compound depends upon the type of ligand and dd transition taking place.
H2O is weak field ligand , which causes small splitting, leading to the d-d transition corresponding green colour, however due to the presence of (en) which ia strong field ligand, the splitting is increased. Due to the change in t2g - eg splitting the colouration of the compound changes from green to blue.
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संबंधित प्रश्न
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Read the passage carefully and answer the questions that follow.
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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).
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