Question

What element forms an ion with an electronic configuration of 1s22s22p63s23p63d104s24p64d105s25p6 (or [xe]) and a –2 charge?

Answer 1

The appropriate response would be Tellurium. For the reason that it can receive a - 2 charge, and when it grabs two electrons, it fills the 5p shell with six electrons, so it will have the electronic arrangement of [Xe]. It cannot be Barium since if it loses two electrons, it will get the electronic configuration of [Xe] when it loses the 6s2 electrons, but it will be a +2 cation, not an anion.

Answer 2

Explanation:

Atomic number of Xenon is 54 and its electronic configuration is $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^{6}4d^{10}5s^{2}5p^{6}$.

When an element gains an electron then it acquires a charge of -1. And, when two electrons are gained by an element then it acquires a charge of -2 and so on.

Tellurium is the element which has 52 electrons and electronic configuration of $Te^{2-}$ is as follows.     $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^{6}4d^{10}5s^{2}5p^{6}$

Thus, we can conclude that tellurium element forms an ion with an electronic configuration of $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^{6}4d^{10}5s^{2}5p^{6}$ and a charge of -2.