The element with the lowest atomic number that has a ground state electronic configuration of (n-1) — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

The general electronic configuration as given in the question at the ground state is- 6 2 ( 1) n d ns . As we know, d electrons start filling with 3d. 2d or 1d does not exist. The lowest electronic configuration that is possible in this general configuration- 6 2 3 4 d s As the outermost electron is in 4th shell, so the element will exist in the fourth period. Thus, the correct option is (c) fourth period.