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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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संबंधित प्रश्न
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The chemistry of the actinoid elements is not so smooth as that of the Lanthanoids. Justify this statement by giving some examples from the oxidation state of these elements.
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(at. no. of Lanthanum = 57 and Lutetium = 71)
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(ii) it has a tendency to attain noble gas configuration
(iii) it has a tendency to attain f 0 configuration
(iv) it resembles Pb4+
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 |
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Nature of bonding in \[\ce{La2O3}\] and \[\ce{Lu2O3}\] .
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La(OH)3 is more basic than Lu(OH)3.
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