Symbol O
Atomic Number 8
Atomic Mass 15.999 g.mol-1
Discovered by Joseph Priestly in 1774

Table of Contents

Chemical Properties of Oxygen

Group 16 Melting point -219 °c
Period 2 Boiling point -183 °c
Block p Density (g cm−3) 0.001308
Atomic number 8 Relative atomic mass 15.999
State at 20°C Gas Key isotopes 16O
Electron configuration [He]2s2 2p4 CAS number 7782-44-7
ChemSpider ID 140526 ChemSpider is a free chemical structure database

What is Oxygen?

  • Oxygen is a member of the chalcogen group on the periodic table. It is an essential element in most combustion processes.
  • It is one of the most abundant elements in the Earth’s crust.

Uses of Oxygen

  • It is used in the production and manufacturing of glass and stone products, and in mining.
  • Special oxygen chambers are used in case of high pressure to increase the partial pressure of oxygen around the patient.
  • The primary applications of oxygen include melting, refining, and manufacturing of steel along with other metals.

Physical Properties of Oxygen

  • The gas is colourless, odourless and insipid in a normal state. Liquid oxygen is slightly paramagnetic. It is reactive and forms oxides with every element except helium, neon, krypton, and argon. It is moderately soluble in water.
  • Dioxygen is one of the common allotropes of oxygen.
  • Trioxygen is the most reactive allotrope of oxygen that would cause damage to lung tissue. This allotrope is termed ozone.

Other Important Information

  • O-16, O-17, and O-18 are the three naturally occurring stable isotopes of Oxygen.
  • Oxygen is characterised by a paramagnetic property.

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Related Elements

Hydrogen Nickel Neon Potassium
Helium Copper Sodium Calcium
Lithium Zinc Magnesium Scandium
Beryllium Gallium Aluminium Titanium
Boron Germanium Silicon Vanadium
Carbon Arsenic Phosphorus Chromium
Nitrogen Selenium Sulphur Manganese
Cobalt Bromine Chlorine Iron
Fluorine Krypton Argon
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