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Question
What are lanthanoids?
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Solution
The series involving the filling of 4f-orbitals following lanthanum La (Z = 57) is called the lanthanoid series. The elements present in this series are called lanthanoids.
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| Column I (Property) | Column II (Element) | |
| (i) | Lanthanoid which shows +4 oxidation state |
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| (ii) | Lanthanoid which can show +2 oxidation state |
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