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प्रश्न
Give reasons:
Transition metals show variable oxidation states.
Account for the following:
Transition metals show variable oxidation states.
Explain giving reasons:
Transition elements exhibit variable oxidation states.
Why do transition elements exhibit variable oxidation states?
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उत्तर १
- The variable oxidation states of transition elements are due to the participation of ns and (n − 1) d-electrons in bonding.
- A lower oxidation state is exhibited when the ns-electrons take part in bonding.
- Higher oxidation states are exhibited when the (n − 1) d-electrons take part in bonding.
- Since there is very little energy difference between these orbitals, both energy levels can be used for bond formation.
Thus, transition elements exhibit variable oxidation states.
उत्तर २
- In transition elements, the 3d and 4s electrons are close in energy and can be lost in different numbers during reactions.
- The involvement of both (n − 1) d and ns electrons in bonding allows multiple oxidation states.
- Stability of oxidation states is influenced by half-filled or fully filled d-subshells, leading to preferred oxidation numbers.
- For example, manganese shows oxidation states from +2 to +7, reflecting this variability.
Hence, transition elements show a wide range of oxidation states because they can lose different numbers of d and s electrons easily.
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संबंधित प्रश्न
Complete the following chemical equations:
`(i) Cr_2O_7^(2-)+6Fe^(2+)+14H^+ ->`
`(ii) 2CrO_4^(2-)+2H^+ ->`
`(iii) 2MnO_4^-+5C_2O_4^(2-)+16H^+ ->`
|
`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.
In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?
Metallic radii of some transition elements are given below. Which of these elements will have highest density?
| Element | \[\ce{Fe}\] | \[\ce{Co}\] | \[\ce{Ni}\] | \[\ce{Cu}\] |
| Metallic radii/pm | 126 | 125 | 125 | 128 |
Transition elements show magnetic moment due to spin and orbital motion of electrons. Which of the following metallic ions have almost same spin only magnetic moment?
(i) \[\ce{Co^{2+}}\]
(ii) \[\ce{Cr^{2+}}\]
(iii) \[\ce{Mn^{2+}}\]
(iv) \[\ce{Cr^{3+}}\]
Reactivity of transition elements decreases almost regularly from Sc to Cu. Explain.
Identify A to E and also explain the reactions involved.
Which of the following ions will exhibit colour in aqueous solution?
Give reason for the following statement:
[Ti(H2O)]3+ is coloured while [Sc(H2O)6]3+ is colourless.
The value of Δ0 for \[\ce{RhCl^{3-}6}\] is 243 KJ/mol which wavelength of light will promote an electron from. The colour of the complex is ______.
