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प्रश्न
How would you account for the following:
There is a greater range of oxidation states among the actinoids than among the lanthanides.
Account for the following:
Actinoids show more number of oxidation states than lanthanoids.
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उत्तर
Actinides exhibit larger oxidation states than lanthanides because of the very small energy gap between 5f, 6d, and 7s subshells as compared to 4f, 5d, and 6s orbitals in the case of lanthanoids. Thus, the outermost electrons get easily excited to the higher energy levels, giving variable oxidation states.
संबंधित प्रश्न
What are chemical twins? Write ‘two’ examples.
Name a member of the lanthanoid series which is well known to exhibit +4 oxidation state.
What are the different oxidation states exhibited by the lanthanoids?
Explain, why lanthanum (Z = 57) forms La3+ ion, while cerium (Z = 58) forms Ce4+ ion?
What is the action of the following on lanthanoids?
a. water
b. Sulphur, heat
c. nitrogen, heat
Match the compounds/elements given in Column I with uses given in Column II.
| Column I (Compound/element) | Column II (Use) | |
| (i) | Lanthanoid oxide | (a) Production of iron alloy |
| (ii) | Lanthanoid | (b) Television screen |
| (iii) | Misch metal | (c) Petroleum cracking |
| (iv) | Magnesium based alloy is constituent of | (d) Lanthanoid metal + iron |
| (v) | Mixed oxides of lanthanoids are employed | (e) Bullets |
| (f) In X-ray screen |
On the basis of Lanthanoid contraction, explain the following:
Trends in acidic character of lanthanoid oxides.
The titanium (Z = 22) compound that does not exist is:-
In lanthanoid the last electron enters (n - 2)f subshell where n is equal to ______.
The lathanide ion that would show colour is ______.
