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प्रश्न
On the basis of Lanthanoid contraction, explain the following:
Trends in acidic character of lanthanoid oxides.
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उत्तर
Acidic or basic character of oxides is related to the nature of oxides. As we move along the lanthanide series from \[\ce{La}\] to \[\ce{Lu}\], the covalent character increases.
Therefore, their basic character decreases or acidic character increases.
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| 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 |
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| (f) In X-ray screen |
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| Column I | Column II | |
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| Mn in oxides is | (d) + 5 | |
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