O2: meaning, definitions and examples

oxygen provider

O2 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.

oxygen

Examples of usage

• Patients with respiratory problems may require O2 therapy.

• Deep sea divers use O2 tanks to breathe underwater.

• O2 is essential for combustion to occur.

• The atmosphere contains approximately 21% O2.

• Plants produce O2 during photosynthesis.