Facts about Oxygen

Liquid oxygen in an unsilvered Dewar flask. Liquid oxygen is blue.

   

Here are 10 interesting facts about the element oxygen. You can find more oxygen facts on the element's periodic table facts page.

1. Animals and plants require oxygen for respiration.
2. Oxygen gas is colorless, odorless, and tasteless.
3. Liquid and solid oxygen are pale blue.
4. Oxygen is a non-metal.
5. Oxygen gas normally is the divalent molecule O₂. Ozone, O₃, is another form of pure oxygen.
6. Oxygen supports combustion.
7. Oxygen is paramagnetic.
8. Approximately 2/3 of the mass of the human body is oxygen.
9. Excited oxygen is responsible for the bright red and yellow-green colors of the aurora.
10. Oxygen was the atomic weight standard for the other elements until 1961 when it was replaced by 
11.  Oxygen forms chemical bonds with almost all other elements, creating the corresponding oxides. For example, rust is actually the formation of iron oxide (Fe₂O₃) and Lime is actually calcium oxide (CaO).
12. Oxygen on Earth actually usually exists in the form of O₂ called dioxygen, but also exists as O₃, ozone, mostly in the atmosphere but also exists on the surface in smog.
13. The O₃ in our atmosphere helps to protect the Earth from UV rays from the Sun. If the UV rays we’re able to pass through the atmosphere unhindered, life would not be able to survive. Ironically O₃ on the surface is harmful to animal lung tissue
14. Oxygen is the 3rd most abundant element by mass in the Universe, behind Hydrogen and Helium, and the most abundant element by mass in the Earth’s crust.
15. O₂, in liquid form and in the presence of a magnetic field, forms a magnet and has been shown to be able to form a bridge, between the two poles of a magnet, capable of supporting its own weight.
16. Aside from being one of the two elements that bond to form water (H₂O), oxygen also dissolves into water, which is the oxygen that fish and other creatures breathe
17. At the present rate of creation, by photosynthesis, and consumption, by respiration and decay, the entire Earth’s oxygen is renewed every 2000 years
18. The bright red color of your blood is because of the oxygen attached to your red blood cells. After those red blood cells have released their oxygen and picked up a Carbon Dioxide (CO₂) you blood turns a dark red, or a maroon color.
19.   Humans inhale more than 6 billion tones of oxygen each year.
20. Oxygen is an element with the chemical symbol O and atomic number 8. 
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