Oxygen forms which ion?

Oxygen forms which ion?

• A. O 2-
• B. O 2+
• C. O 0
• D. O -

Answer: (A)

Gaining electrons to fill its outer shell is what oxygen typically does in compounds. Oxygen has six electrons in its outer level, so it tends to gain two more to reach a stable eight. When it gains two electrons, it becomes O2−, the oxide ion. This is the common ionic form of oxygen in many compounds, like metal oxides. Losing electrons to become a positive oxygen ion is not a normal, stable form for oxygen in usual chemistry, and remaining neutral would mean it isn’t an ion at all. While there are other oxygen species in special contexts, the most typical ion oxygen forms is the oxide ion with a −2 charge.

Gaining electrons to fill its outer shell is what oxygen typically does in compounds. Oxygen has six electrons in its outer level, so it tends to gain two more to reach a stable eight. When it gains two electrons, it becomes O2−, the oxide ion. This is the common ionic form of oxygen in many compounds, like metal oxides. Losing electrons to become a positive oxygen ion is not a normal, stable form for oxygen in usual chemistry, and remaining neutral would mean it isn’t an ion at all. While there are other oxygen species in special contexts, the most typical ion oxygen forms is the oxide ion with a −2 charge.