Last updated on January 8th, 2023
Oxygen (after hydrogen and helium) is the third most abundant element in the universe. Oxygen is atomic number 8 and atomic weight 15.999. In gaseous appearance, it is colorless and in the liquid and solid state, it is pale blue in color. Its symbol is O.
With these facts about oxygen, let us understand more in detail about this life supporting element which is useful in many fundamental ways to millions of living species on the planet earth.
33 Important facts about Oxygen
1. Oxygen was discovered in 1774 by Joseph Priestley in England. However, Carl Wilhelm Scheele (he called it “fire air”) discovered the element two years earlier, but the credit for the discovery of the element is often given to Joseph Priestley (maybe because Wilhelm did not publish his findings prior to Joseph’s).[1,2]
2. Oxygen makes up nearly 21% of the earth’s atmosphere, two-thirds of the mass of the human body, and nearly half of the mass of the earth’s crust. Almost 90% of the Earth’s crust is made up of these five elements: aluminum, silicon, calcium, iron, and oxygen.[1,4]
3. Oxygen is a highly reactive element. In fact, it is the most non-reactive of the non-metallic elements. Non-metals are located in groups 14, 15 and 16 of the Periodic Table.[1,2]
4. The first oxygen on earth is estimated to have been contributed by Cyanobacteria that consume carbon dioxide and exhale oxygen.[2,3]
5. The element derives its name from the Greek “oxy” meaning acid and “genes” meaning forming. The name of the element was given by the French scientist, Antoine Lavoisier.
6. Interestingly, a molecule of oxygen can withstand the pressure which is nineteen million times higher than the atmospheric pressure.
7. Rocks on earth are about 46% oxygen by weight. Oxygen content in the rocks is in the form of silicon dioxide, which is commonly known as sand.
8. Oxygen in the human body is present in fats, carbohydrates, and DNA.
9. Oxygen belongs to the Chalcogen family (group 16 of the periodic table). Some other group 16 elements include sulfur, selenium, tellurium, and polonium.
10. Leonardo da Vinci also confirmed the existence of some other constituent in the air when he realized that a fraction of air is consumed in combustion and respiration.
11. Oxygen supports the burning of other substance however pure oxygen itself does not burn.
12. Under normal conditions, freshwater contains 6.04 ml of oxygen per liter. Seawater, on the other hand, contains only 4.95 ml of oxygen per liter.
13. When the dissolved oxygen in water is below 3mg/l, the water is called hypoxic. And when it is 0.5 mg/l, it is called anoxic.
14. Oxygen is paramagnetic (according to dictionary.com – a body or substance that, placed in a magnetic field, possesses magnetization in direct proportion to the field strength; a substance in which the magnetic moments of the atoms are not aligned.
15. Except for helium and neon, oxygen can form compounds with every other element.
16. Earth is the only planet in the solar system that has enough oxygen for the living beings to survive.
17. Three atoms of Oxygen combine and make a molecule of Ozone (an allotrope of oxygen). Ozone is helpful in preventing the unwanted rays from the sun from entering the earth’s atmosphere.
18. Oxygen in gaseous form is colorless, odorless and tasteless.
19. Oxygen is expected to be in existence on earth for the past 2.3 to 2.4 billion years.
20. Liquid oxygen has a freezing point of -218.79 °C and a boiling point of −182.96 °C.
21. A cool fact about oxygen is that oxygen dissolves faster in cool water than it does in warm water.
22. When we breathe, oxygen enters alveoli, in the lungs. From there it is picked up by the red blood cells. The hemoglobin in the red blood cells joins oxygen and carries it around the body.
23. The lung consumes about 5% of whole-body oxygen uptake.
24. Did you know that a human being uses about 550 liters of pure oxygen (19 cubic feet) per day?
25. Photosynthesis (a process used by plants and other organisms to convert light energy into chemical energy) releases oxygen into the atmosphere while decay and respiration remove oxygen from the atmosphere.
26. The solubility of oxygen, or its ability to dissolve in water, decreases as water temperature and salinity increase.
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