Question

a m²⁺ ion has two electrons in the 3d subshell and is derived from a metal in the first transition metal series. based on the description provided, enter a chemical symbol for what element m might be.

Explanation:

Step1: Determine electron configuration of $M^{2 +}$

The $M^{2+}$ ion has two electrons in the 3d sub - shell. The electron configuration of $M^{2+}$ is $[Ar]3d^{2}$.

Step2: Determine electron configuration of neutral M

A $M^{2+}$ ion is formed by losing 2 electrons from the neutral atom M. So, to get the electron configuration of M, we add 2 electrons back. The electron configuration of M is $[Ar]3d^{4}4s^{2}$.

Step3: Identify the element

The element with the electron configuration $[Ar]3d^{4}4s^{2}$ is chromium (Cr).

Answer:

Cr