Periodic table / Oxygen

Overview

Oxygen is a chemical element with symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table and is a highly reactive nonmetal and oxidizing agent that readily forms compounds (notably oxides) with most elements. By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium.

Electron configuration

The electron configuration of Oxygen is [He] 2s2 2p4, with electron shells of 2, 6.

Physical and chemical properties

Oxygen is classified as a nonmetal. It has an atomic mass of 15.999 and exists as a gas at standard conditions.

Real-world uses of Oxygen

Oxygen plays an important role in chemistry and biology, and is used in industrial processes, manufacturing, or as a key component of compounds essential to life.

Interesting facts about Oxygen

• Oxygen has the atomic number 8 and chemical symbol O.
• It belongs to period 2, group 16 of the periodic table.
• Oxygen was discovered by Carl Wilhelm Scheele.

Explore Oxygen interactively

Want to compare Oxygen with other elements or see it highlighted on the full table? Open the interactive periodic table and click on O to explore properties, trends, and neighboring elements. You can also test your knowledge with our periodic table quiz game.