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प्रश्न
What is the action of the following on lanthanoids?
a. water
b. Sulphur, heat
c. nitrogen, heat
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उत्तर
- Action of water on lanthanoids: Reaction of water with lanthanoids gives ionic and basic lanthanide hydroxides (Ln(OH)3) with liberation of H2 gas.
Ln + 3H2O → Ln(OH)3 + 3H2 - Action of sulphur on lanthanoids: Heating of sulphur with
lanthanoids gives lanthanide sulphide (Ln2S3).
\[\ce{2Ln + 3S ->[\Delta] Ln2S3}\] - Action of nitrogen on lanthanoids: Reaction of nitrogen with lanthanoide gives lanthanide nitride (LnN).
\[\ce{2Ln + N2 ->[\Delta] 2LnN}\]
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संबंधित प्रश्न
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Explain the cause of Lanthanoids contraction.
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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?
(i) U (Atomic no. 92)
(ii) Np (Atomic no.93)
(iii) Pu (Atomic no. 94)
(iv) Am (Atomic no. 95)
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 |
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| (f) In X-ray screen |
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