ExamBro
ExamBro
TS EAMCET · Chemistry · d and f Block Elements

What is the effect of lanthanoid contraction in lanthanoid series of elements with increasing atomic number?

  1. A Decreases in atomic radii
  2. B Increases in atomic radii
  3. C Decreases in melting point
  4. D Increases in melting point
Verified Solution

Answer & Solution

Correct Answer

(A) Decreases in atomic radii

Step-by-step Solution

Detailed explanation

Lanthanide contraction is the steady decrease in size of atoms and ions of rare earth elements with increasing atomic number from lanthanum. (Atomic number \(=57\) ) It is caused by poor shielding effect of \(4 f\)-electrons. In row 3, we have \(4 f\)-electrons which do not…