What is the electron configuration for Sodium (Na)?

The correct electron configuration for sodium (Na) is indeed 1s² 2s² 2p⁶ 3s¹. Sodium has an atomic number of 11, which means it has 11 electrons. The electron configuration describes how these electrons are distributed among the different atomic orbitals.

In the configuration 1s² 2s² 2p⁶, the first two electrons fill the 1s orbital, the next two electrons fill the 2s orbital, and the subsequent six electrons completely fill the 2p orbital, which is the maximum capacity of that sublevel. After these ten electrons are accounted for, the remaining electron occupies the 3s orbital, represented as 3s¹. This distribution reflects the order of orbital filling according to the Aufbau principle, which states that electrons fill from the lowest energy level to the highest.

The configuration reflects both the number of electrons present in each subshell and adheres to the established rules of electron distribution, which include Pauli's exclusion principle and Hund's rule. Therefore, the first option accurately represents the electron configuration of sodium.