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प्रश्न
Predict which of the following will be coloured in the aqueous solution?
Ti3+, V3+, Cu+, Sc3+, Mn2+, Fe3+ and Co2+. Give reasons for each.
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उत्तर
Only the ions that have electrons in the d-orbital and for which the d-d transition is possible will be coloured. The ions in which d-orbitals are empty or completely filled will be colourless as no d-d transition is possible in those configurations.
| Element | Atomic Number | Ionic State | Electronic configuration in ionic state |
| Ti | 22 | Ti3+ | [Ar] 3d1 |
| V | 23 | V3+ | [Ar] 3d2 |
| Cu | 29 | Cu+ | [Ar] 3d10 |
| Sc | 21 | Sc3+ | [Ar] |
| Mn | 25 | Mn2+ | [Ar] 3d5 |
| Fe | 26 | Fe3+ | [Ar] 3d5 |
| Co | 27 | Co2+ | [Ar] 3d7 |
From the above table, it can be easily observed that only Sc3+ has an empty d-orbital and Cu+ has completely filled d-orbitals. All other ions, except Sc3+ and Cu+, will be coloured in aqueous solution because of d-d transitions.
संबंधित प्रश्न
What are interstitial compounds?
Which of the following cations are coloured in aqueous solutions and why ?
Sc3+, V3+, Ti4+, Mn2+ (At. Nos. Sc = 21, V = 23, Ti = 22, Mn = 25)
Why is the highest oxidation state of a metal exhibited in its oxide or fluoride only?
To what extent do the electronic configurations decide the stability of oxidation states in the first series of the transition elements? Illustrate your answer with examples.
In what way is the electronic configuration of the transition elements different from that of the non-transition elements?
How would you account for the following:
The d1 configuration is very unstable in ions.
Which metal in the first series of transition metals exhibits +1 oxidation state most frequently and why?
An antifriction alloy made up of antimony with tin and copper, which is extensively used in machine bearings is called _______.
(A) Duralumin
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(C) Spiegeleisen
(D) Amalgam
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Zr (Z = 40) and Hf (Z = 72) have almost identical radii.
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The complex showing a spin-span magnetic moment of 2.82 B.M. is :-
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Physical and chemical properties of the 4d and 5d series of the transition elements are quite similar to expected.
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(Round off to the nearest integer).
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