O
Oxygen
Element 8 · Nonmetal · Period 2, Group 16
Gas · Discovered 1774
Atomic Properties
| Atomic Number | 8 |
| Atomic Mass | 15.999u |
| Electron Configuration | [He]2s2 2p4 |
| Electronegativity | 3.44Pauling |
| Atomic Radius | 152pm |
| Ionization Energy | 13.618eV |
| Electron Affinity | 1.461eV |
| Oxidation States | -2 |
Physical Properties
| Standard State | Gas |
| Melting Point | 54.36K |
| Boiling Point | 90.2K |
| Density | 0.001429g/cm³ |
| Group Block | Nonmetal |
| Year Discovered | 1774 |