Oxygen is a chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium.
Properties of Oxygen:
Physical State: Oxygen is a colorless, odorless, and tasteless gas at room temperature and pressure.
Chemical Reactivity: It is highly reactive and forms compounds with almost all other elements, as well as with many organic compounds.
Role in Combustion: Oxygen supports combustion, and many materials ignite and burn more vigorously in its presence.
Role in Ozone Layer: In the Earth's atmosphere, oxygen plays a crucial role in the formation and maintenance of the ozone layer, which protects life on Earth by filtering out harmful ultraviolet radiation from the sun.
Study Guide:
Here are some key points to remember about oxygen:
From Molecules to Organisms: Structures and Processes
Students who demonstrate understanding can:
Construct an argument that plants and animals have internal and external structures that function to support survival, growth, behavior, and reproduction.