What is the electron configuration for Selenium (Se)?

Selenium (Se) has an atomic number of 34, which means it has 34 electrons. To determine the electron configuration, we need to distribute these electrons into the available atomic orbitals according to the Aufbau principle, Hund's rule, and the Pauli exclusion principle.

Starting from the lowest energy level, the distribution begins as follows:

• The 1s orbital can hold up to 2 electrons: 1s²

• The 2s orbital can also hold 2 electrons: 2s²

• The 2p orbitals can hold up to 6 electrons: 2p⁶

• The 3s orbital holds another 2 electrons: 3s²

• The 3p orbitals can accommodate 6 electrons: 3p⁶

• Moving to the next shell, the 4s orbital can hold 2 electrons: 4s²

• After filling the 4s, the 3d orbitals are filled next with 10 electrons: 3d¹⁰

• Finally, we need to account for the remaining 4 electrons in the 4p orbitals, which leads us to 4p⁴.

Combining these,