8 O 15.999

Oxygen

DIATOMIC NONMETAL

Phase: Gas

Discovered: Carl Wilhelm Scheele

Block: P

Summary

Oxygen is a chemical element with symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table and is a highly reactive nonmetal and oxidizing agent that readily forms compounds (notably oxides) with most elements. By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium.

Source: Wikipedia

Physical Properties

Atomic Mass 15.999 u

Density 1.429 g/cm³

Melting Point 54.36 K

Boiling Point 90.188 K

Molar Heat N/A

Electron Affinity 140.976 kJ/mol

Ionization Energies

1^st: 1313.9 kJ/mol

2^nd: 3388.3 kJ/mol

3^rd: 5300.5 kJ/mol

4^th: 7469.2 kJ/mol

5^th: 10989.5 kJ/mol

6^th: 13326.5 kJ/mol

7^th: 71330 kJ/mol

8^th: 84078 kJ/mol