Curated category
Breathing gases
- OxygenOxygen is the third most abundant chemical element in the universe, trailing only hydrogen and helium. About 0.9% of the Sun's mass consists of oxygen.
- Atmosphere of EarthA dry breath of air contains 78.08% nitrogen and 20.95% oxygen by mole fraction. Argon makes up 0.93% of the mixture, while carbon dioxide accounts for just…