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प्रश्न
How would you account for the following:
The d1 configuration is very unstable in ions.
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उत्तर
In ions, the d1 configuration is unstable, but after losing one electron, it becomes more stable due to the vacant d-orbitals. All elements with d1 configuration are reduced or undergo disproportionation. e.g.,
\[\ce{3\overset{+6}{\underset{3d^1}{Mn}}O^2-_4 + 4H+ -> 2\overset{+7}{\underset{3d^0}{Mn}}O^-_4 + \overset{+4}{Mn}O2 + 2H2O}\]
संबंधित प्रश्न
What are interstitial compounds?
How would you account for the irregular variation of ionization enthalpies (first and second) in the first series of the transition elements?
What are the characteristics of the transition elements and why are they called transition elements?
In what way is the electronic configuration of the transition elements different from that of the non-transition elements?
The transition metals show _________ character because of the presence of unpaired· electrons and Cu+ is ____________ because of its electronic configuration is [Ar]3d10
Explain why transition metals and their compounds act as a catalyst.
Give reasons for the following:
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Fill in the blanks by choosing the appropriate word(s) from those given in the brackets:
(activation energy, Threshold energy, increased, lowered, partially, full, d-d transition, Benzoic acid, benzaldehyde)
Only those transition metal ions will be coloured which have ______ filled d-orbitals facilitating ______.
On the basis of the figure given below, answer the following questions:
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- Why do transition metals of 3d series have lower melting points as compared to 4d series?
- In the third transition series, identify and name the metal with the highest melting point.
If enthalpies of formation of C2H4(g), CO2(g) and H2O(l) at 25°C and 1 atm pressure are 52, – 394 and – 286 kJ/mol respectively, the change in ethalpy for combustion of C2H4 is equal to
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Among the following pairs of ions, the lower oxidation state in aqueous solution is more stable than the other in:-
Agcl is soluble in NH4OH. The solubility is due to the information of:-
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Physical and chemical properties of the 4d and 5d series of the transition elements are quite similar to expected.
Which of the following ions acts as a typical transition metal ion?
Assertion (A): Transition metals have high enthalpy of atomisation.
Reason (R): Greater number of unpaired electrons in transition metals results in weak metallic bonding.
Assertion (A): Transition metals show their highest oxidation state with oxygen.
Reason (R): The ability of oxygen to form multiple bonds to metals.
