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Classification of Elements and Periodicity in Properties — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryClassification of Elements and Periodicity in Properties2 Marks
Question
Lanthanoids and actinoids are placed in separate rows at the bottom of periodic table. Explain the reason for this arrangement.
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Answer

Lanthanoids and actinoids resemble with each other but do not resemble any other group elements, therefore, they are kept at bottom of periodic table. They show horizontal similarity among each other.

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