Oxygen is a chemical element; it has the symbol O and its atomic number is 8. It is a member of the chalcogen group in the periodic table. It is highly reactive, a nonmetal, and a potent oxidizing age
Liquid oxygen (O2 at below −183 °C)
Among several contemporaries who had made discoveries independently from one another, Joseph Priestley was the first to publish his findings on oxygen.
Antoine Lavoisier discredited the phlogiston theory.
Robert H. Goddard and a liquid-oxygen–gasoline rocket
Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common eleme
Oxygen
…air', which is essential to combustion and respiration, and azote (from Greek ἄζωτον 'lifeless'), which did not support either. Azote later became nitrogen in English, although it has kept the earlier name in French and several other European languages. Lavoisier renamed "vital air" to oxygène in 1777 from…
Liquid nitrogen (N2 at below −196 °C)
Daniel Rutherford, discoverer of nitrogen
Molecular orbital diagram of dinitrogen molecule, N2. There are five bonding orbitals and two antibonding orbitals (marked with an asterisk; orbitals involving the inner 1s electrons not shown), giving a total bond order of three.