Lanthanoid Contraction Phenomenon

Lose (n – 1) d electrons before ns electrons

Gain ns electrons before (n – 1) d electrons

Simultaneously lose ns and (n – 1) d electrons

Lose ns electrons before (n – 1) d electrons (correct)

Increase the nuclear charge on 4s electrons

Shield the 4s electrons more effectively than outer shell electrons (correct)

Shield the 4s electrons less effectively than outer shell electrons

Have no effect on the shielding of 4s electrons

Remain constant

Decrease more rapidly

Decrease less rapidly (correct)

Increase along the series

<p>Decreases atomic radii</p> Signup and view all the answers

<p>Due to the shielding effect of 3d electrons</p> Signup and view all the answers

<p>Doubly or more highly charged ions</p> Signup and view all the answers

<p>Due to the d5 configuration of these ions</p> Signup and view all the answers

<p>Attraction of each electron towards nucleus, repulsion between electrons, and exchange energy</p> Signup and view all the answers