O2
Definition
O2 or Oxygen gas is a colorless, odorless reactive gas that forms about 21% of the earth's atmosphere. It supports combustion and respiration in most living organisms.
Related terms
Oxidation: A chemical reaction that involves the loss of electrons or an increase in oxidation state by a molecule, atom, or ion.
Respiration: The metabolic process where organisms inhale oxygen from their environment to produce energy from food molecules.
Ozone (O3): An allotrope of oxygen that consists of three oxygen atoms bonded together.
"O2" appears in:
Subjects (1)
AP Chemistry
Study guides (3)
AP Biology - 2.5 Membrane Permeability
AP Biology - 3.5 Photosynthesis
AP Biology - 3.6 Cellular Respiration
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Resources
Cram Mode
AP Score Calculators
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Glossary
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Crisis Text Line
Help Center
© 2024 Fiveable Inc. All rights reserved.
AP® and SAT® are trademarks registered by the College Board, which is not affiliated with, and does not endorse this website.