What is the element associated with the electron configuration [Kr] 5s^2 4d^10 5p^2?

The correct answer is associated with the element that corresponds to the given electron configuration [Kr] 5s^2 4d^10 5p^2, which represents a total of 8 valence electrons in its outermost principal energy level (5). This configuration shows that the element has filled the 4d subshell with 10 electrons and has 2 electrons in the 5s subshell, followed by 2 more in the 5p subshell.

To identify the specific element, one needs to count the total number of electrons. The configuration begins with the noble gas krypton ([Kr]), which has 36 electrons, followed by 2 electrons in the 5s subshell and 10 in the 4d subshell, plus another 2 in the 5p subshell. Therefore, the total number of electrons is:

36 (from Kr) + 2 (from 5s) + 10 (from 4d) + 2 (from 5p) = 50 electrons.

The element with atomic number 50 is tin (Sn), which aligns perfectly with the provided electron configuration of [Kr] 5s^2 4d^10 5p