Which among the following electronic configurations belong to d-block elements? A. [ Ar ] 3 d ¹⁰ 4 s ^1 B. [ Xe ] 4 f ¹⁴ 5 d ¹⁰ 6 s ^2 6 p ^1 C. [ Kr ] 4 d ¹⁰ 5 s ^0 D. [ Xe ] 4 f ^7 5 d ^1 6 s ^2 E. [ Ar ] 3 d ¹⁰ 4 s ^2 4 p ^6 Choose the correct answer from the options given below:

Step-by-step solution

The block of an element is determined by the subshell in which the last (differentiating) electron enters. A. [ Ar ] 3 d ¹⁰ 4 s ^1 : The last electron enters the 3d subshell (anomalous configuration of Copper). It is a d-block element. B. [ Xe ] 4 f ¹⁴ 5 d ¹⁰ 6 s ^2 6 p ^1 : The last electron enters the 6p subshell. It is a p-block element, despite having a completely filled 5d subshell. C. [ Kr ] 4 d ¹⁰ 5 s ^0 : The last electron enters the 4d subshell (anomalous configuration of Palladium). It is a d-block elemen