* Krypton (Kr) has an atomic number of 36, meaning it has 36 protons and 36 electrons in its neutral state.

* -2 charge indicates that the ion has gained two electrons.

* To have the same electron configuration as Kr, the ion must also have 36 electrons.

Therefore, the neutral atom must have 34 electrons (36 - 2). An atom with 34 electrons has an atomic number of 34.

The element with an atomic number of 34 is Selenium (Se).

So, the ion with the electronic configuration of Kr and a -2 charge is the selenide ion (Se²⁻).