-Which element,indicated by letter on the periodic table above,has a 2+ ion with the electron configuration [Ar]3d¹⁰?

Question

-Which element,indicated by letter on the periodic table above,has a 2+ ion with the electron configuration [Ar]3d¹⁰? A)A B)B C)C

Quizplus · Accepted Answer

The electron configuration given, [Ar]3d^5, indicates an ion that has lost two electrons compared to its neutral state. Starting from the neutral state, the element would have the electron configuration [Ar]3d^7. This corresponds to Cobalt (Co), which is in the 9th group of the transition metals (counting from Scandium). The correct choice is the element that, when it loses two electrons, would have the configuration of [Ar]3d^5, which is Cobalt (Co).

-Which Element,indicated by Letter on the Periodic Table Above,has a 2