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Question
Which among the following pairs of elements is 'not' an example of chemical twins?
Options
Zr and Hf
Nb and Ta
Mo and W
Ta and Re
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Solution
Ta and Re
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RELATED QUESTIONS
Define lanthanoid contraction.
Account for the following :
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a. water
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General electronic configuration of actinoids is `(n-2)f^(1-14)(n - 1)d^(0-2)ns^2`.Which of the following actinoids have one electron in 6d orbital?
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Although +3 is the characteristic oxidation state for lanthanoids but cerium also shows +4 oxidation state because:
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Match the statements given in Column I with the oxidation states given in Column II.
| Column I | Column II | |
| (i) | Oxidation state of Mn in MnO2 is | (a) + 2 |
| (ii) | Most stable oxidation state of Mn is | (b) + 3 |
| (iii) | Most stable oxidation state of | (c) + 4 |
| Mn in oxides is | (d) + 5 | |
| (iv) | Characteristic oxidation state of lanthanoids is | (e) + 7 |
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Stability of the complexes of lanthanoids.
On the basis of Lanthanoid contraction, explain the following:
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On the basis of Lanthanoid contraction, explain the following:
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The titanium (Z = 22) compound that does not exist is:-
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La(OH)3 is more basic than Lu(OH)3.
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