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Q · Classification of Elements Hard · 45s
The lanthanide contraction primarily affects which block?
TopicClassification of Elements
Question Typemultiple choice
DifficultyHard
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Poor shielding by 4f electrons causes decreasing radii across lanthanides.
Final Answer: Option D - f-block