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प्रश्न
What can be inferred from the magnetic moment value of the following complex species?
| Example | Magnetic Moment (BM) |
| K2[MnCl4] | 5.9 |
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उत्तर
Magnetic Moment (μ) = `sqrt(n(n + 2))` BM
When n = 1, μ = `sqrt(1(1 + 2))` = 1.73 BM ≈ 2
When n = 2, μ = `sqrt(2(2 + 2)` = 2.83 BM ≈ 3
When n = 3, μ = `sqrt(3(3 + 2))` = 3.87 BM ≈ 4
When n = 4, μ = `sqrt(4(4 + 2))` = 4.90 BM ≈ 5
When n = 5, μ = `sqrt(5(5 + 2))` = 5.92 BM ≈ 6
K2[MnCl4]: μ = 5.9 BM, Mn2+ ion has 5 unpaired electrons. Its orbital diagram is:
| 3d | ||||
| ↑↓ | ↑ | ↑ | ↑ | ↑ |
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संबंधित प्रश्न
|
`E_((M^(2+)/M)` |
Cr | Mn | Fe | Co | Ni | Cu |
| -0.91 | -1.18 | -0.44 | -0.28 | -0.25 | -0.34 |
From the given data of E0 values, answer the following questions :
(1) Why is `E_(((Cu^(2+))/(Cu)))` value exceptionally positive
(2) Why is `E_(((Mn^(2+))/(Mn)))` value is highly negative as compared to other elements
(3) Which is the stronger reducing agents Cr2+ or Fe2+ ? Give Reason.
Out of Mn3+ and Cr3+, which is more paramagnetic and why ?
(Atomic nos. : Mn = 25, Cr = 24)
For M2+/M and M3+/M2+ systems, the E° values for some metals are as follows:
| Cr2+/Cr | −0.9 V |
| Mn2+/Mn | −1.2 V |
| Fe2+/Fe | −0.4 V |
| Cr3/Cr2+ | −0.4 V |
| Mn3+/Mn2+ | +1.5 V |
| Fe3+/Fe2+ | +0.8 V |
Use this data to comment upon:
- The stability of Fe3+ in acid solution as compared to that of Cr3+ or Mn3+ and
- the ease with which iron can be oxidised as compared to a similar process for either chromium or manganese metal.
How would you account for the following:
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Reason (R): Greater number of unpaired electrons in transition metals results in weak metallic bonding.
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\[\ce{3MnO^{2-}4 + 4H^+ -> \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{} + 2H2O}\]
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Transition metals possess a great tendency to form complex compounds.
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