* Argon (Ar) has an atomic number of 18, meaning it has 18 protons and 18 electrons. Its electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁶.

* A 2+ ion means the element has lost two electrons.

* Same electronic configuration as Ar means the element, after losing two electrons, will have the same number of electrons as Argon.

Therefore, the element we're looking for must have 20 electrons in its neutral state (18 + 2). This corresponds to Calcium (Ca), which has an atomic number of 20.

Explanation:

* Calcium (Ca) has an electron configuration of 1s² 2s² 2p⁶ 3s² 3p⁶ 4s².

* When it loses two electrons from its outermost 4s orbital, it becomes Ca²⁺ with the electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶, which is the same as Argon.