Question

What is the general electronic configuration of d-block elements?

(a) (n-1)d^1-10ns^0-2

(b) ns^2np^1-6

(c) (n–2)f^1–14(n–1)d^0–10ns^2

(d) ns^1-2

This question was addressed to me during an online interview.

The doubt is from Position of the Periodic Table topic in division D and F-Block Elements of Chemistry – Class 12

Answer 1

Correct choice is (a) (n-1)d^1-10ns^0-2

Easiest explanation: D-block elements are so-called since, in them, 3d, 4d, 5d and 6d subshells are incomplete and the last electron enters the (n-1)d orbital, i.e., penultimate (last but one) shell. Their general electronic configuration is (n-1)d^1-10ns^0-2, where n is the outermost shell.