Question

Which of the following statement is correct?

(a) The properties of various actinoids are very similar

(b) 4f and 5f orbitals are equally shielded

(c) D-block elements show irregular and erratic chemical properties

(d) 4d and 5d orbitals are equally shielded

The question was asked in quiz.

I'd like to ask this question from Electronic Configurations of the D-Block Elements in chapter D and F-Block Elements of Chemistry – Class 12

Answer 1

Right answer is (c) D-block elements show irregular and erratic chemical properties

For explanation I would say: There is very little variance in the atomic size of the actinoids and so, they show similar properties. 4f and 5f orbitals belong to different energy levels and so are unequally shielded. The same applies to the 4d and 5d orbitals. The d-block elements are known to show irregular and erratic chemical properties.