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The d-And-f-Block Elements
Question
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The correct increasing order of ionic radii of the following Ce3+, La3+, Pm3+ and Yb3+ is 

  • Yb3+ < Pm3+< Ce3+<La3+

  • Ce3+< Yb3+<Pm3+<La3+

  • Yb3+< Pm3+< La3+<Ce3+

  • Pm3+ < La3+< Ce3+ < Yb3+

Answer

A.

Yb3+ < Pm3+< Ce3+<La3+

Due to the lanthanide contraction size of +3 ions decreases from La3+ to Lu3+

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Some More Questions From The d-And-f-Block Elements Chapter

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