Question

Identify the incorrect statement among the following:

(a) Lanthanoid contraction is the accumulation of successive shrinkages.

(b) As a result of lanthanoid contraction, the properties of 4d series of the transition elements have no similarities with the 5d series of elements.

(c) Shielding power of 4f electrons is quite weak.

(d) There is a decrease in the radii of the atoms or ions as one proceeds from La to Lu.

Answer 1

Correct option (b) As a result of lanthanoid contraction, the properties of 4d series of the transition elements have no similarities with the 5d series of elements.

Explanation :

In each vertical column of transition elements, the elements of second and third transition series resemble each other more closely than the elements of first and second transition series on account of lanthanide contraction. Hence the properties of elements of 4d series of the transition elements resemble with the properties of the elements of 5d series of the transition elements.