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The d & f Block Elements — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements3 Marks
Question
  1. Write the electronic configuration of the element with atomic number 102.
  2. What is lanthanoid contraction? What is its effect on the chemistry of the elements which follow the lanthanoids?
✓

Answer

  1. [Rn] 5f147s2.
  2. The steady decrease in atomic size of lanthanoids with increase in atomic number due to filling of electrons in inner orbitals.

Due to lanthanoid contraction the properties of 4d & 5d series elements become nearly same.

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