Question

Identify the incorrect statement among the following -

• A. d-block elements shows irregular and erratic chemical properties among themselves
• B. La and Lu have partially filled d-orbitals and no other partially filled orbitals
• C. The chemistry of various lanthanoids is very similar
• D. 4f and 5f-orbitals are equality shielded

Answer 1

The correct option is D 4f and 5f-orbitals are equality shielded

(a) d-block elements have differenr valence shell electronic configurations and thus based on that different chemical properties too. Hence it shows irregular and erratic chemical properties.

(b) The electronic configuration of $La$ is $\left[Xe\right]5d^{1}6s^2$
The electronic configuration of $Lu$ is $\left[Xe\right]4f^{14}5d^{1}6s^2$. Thus La and Lu have partially filled d-orbitals and no other partially filled orbitals.

(c) The most common oxidation state of all the lanthanoids is +3 and also they have similar size. Thus the chemistry of various lanthanoids is very similar .

(d) 4f orbital is nearer to the nucleus as compared to 5f orbital. Shielding of 4f is more than 5f orbitals.