Write the electron configuration for each ion. a. O^2-

Electron configuration describes the distribution of electrons in an atom or ion's atomic orbitals. It is represented using a notation that indicates the energy levels and sublevels occupied by electrons. For example, the electron configuration of neutral oxygen (O) is 1s² 2s² 2p⁴, which shows how its electrons are arranged in different energy levels.

Ionic charge refers to the electrical charge that an atom or molecule acquires when it gains or loses electrons. In the case of O²⁻, the oxygen atom has gained two additional electrons, resulting in a negative charge. This change in electron count alters the electron configuration, as the total number of electrons now exceeds the number of protons in the nucleus.

Valence electrons are the outermost electrons of an atom and are crucial for determining its chemical properties and reactivity. For oxygen, the valence electrons are found in the second energy level (2s² 2p⁴). When forming ions, the gain or loss of valence electrons directly influences the atom's stability and its ability to bond with other elements.