Example 7.2: Determining the Electronic Structure of Anions

Selenium and iodine are two essential trace elements that form anions. Write the electron configurations of the anions.

Solution

\(\ce{ Se^2–: [Ar] 3d^10 4s^2 4p^6}\)

\(\ce{ I^–: [Kr] 4d^10 5s^2 5p^6}\)