Question

The size of hafnium is almost similar to that of zirconium, this is due to :

• A. increase in size as expected
• B. decrease in size as expected
• C. lanthanide contraction
• D. similar chemical properties

Answer 1

Answer: (C)

lanthanide contraction

Due to poor shielding effect of 4f electrons, the outer electrons experience a greater effective nuclear charge and the size of the element contracts.

This contraction is known as lanthanide contraction.

Due to lanthanide contraction, 5th and 6th-period transition series elements have similar sizes.

Thus, the size of hafnium is almost similar to that of zirconium.

Hence the option C is correct.