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Question
Name an important alloy which contains some of the lanthanoid metals. Mention its uses.
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Solution
Misch metal is an alloy that contains some lanthanoid metals. It contains 95% lanthanoid metals, 5% iron and traces of S, C, Ca and Al. Misch metal is used in Mg-based alloys to produce bullets, shells, and lighter flint. It is used as a reducing agent in metallurgical operations. Magnesium alloys containing about 30% misch metal and 1% Zr are used for making parts of a jet engine
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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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| (v) | Mixed oxides of lanthanoids are employed | (e) Bullets |
| (f) In X-ray screen |
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| Column I (Property) | Column II (Element) | |
| (i) | Lanthanoid which shows +4 oxidation state |
(a) Pm |
| (ii) | Lanthanoid which can show +2 oxidation state |
(b) Ce |
| (iii) | Radioactive lanthanoid | (c) Lu |
| (iv) | Lanthanoid which has 4f7 electronic configuration in +3 oxidation state |
(d) Eu |
| (v) | Lanthanoid which has 4f14 electronic configuration in +3 oxidation state |
(e) Gd |
| (f) Dy |
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The lathanide ion that would show colour is ______.
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La(OH)3 is more basic than Lu(OH)3.
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