Question
Identify the incorrect statement among the following.
A.
$$4f$$ and $$5f$$ orbitals are equally shielded.
B.
$$d$$ - Block elements show irregular and erratic chemical properties among themselves.
C.
$$La$$ and $$Lu$$ have partially filled $$d$$ - orbitals and no other partially filled orbitals.
D.
The chemistry of various lanthanoids is very similar.
Answer :
$$4f$$ and $$5f$$ orbitals are equally shielded.
Solution :
The decrease in the force of attraction exerted by the nucleus on the valence electrons due to presence of electrons in the inner shells is called shielding effect. A $$4f$$ orbital is nearer to the nucleus than $$5f$$ orbital. Hence shielding of $$4f$$ is more than $$5f.$$