Compare Fluorine vs Astatine
Comparing Fluorine (F) and Astatine (At). Atomic numbers 9 and 85 with atomic masses 18.998 u and 210 u, classified as nonmetal and metalloid. Below: a side-by-side comparison of their physical, atomic, electron-configuration and historical properties, including density, melting and boiling points, ionization energies, oxidation states and discovery history.
Periodic properties of the elements
| Fluorine | Astatine | |
|---|---|---|
| Symbol | F | At |
| Atomic number | 9 | 85 |
| Group | 17 | 17 |
| Period | 2 | 6 |
| Block | p | p |
| Element category | Nonmetal | Metalloid |
Physical properties
| Fluorine | Astatine | |
|---|---|---|
| Phase at STP | Gas | Solid |
| Density | 1.696 g/cm3 | 6.35 g/cm3 |
| Atomic weight | 18.9984 u | 210 u |
| Melting point | 53.48 K -219.67 °C -363.406 °F | 575 K 301.85 °C 575.33 °F |
| Boiling point | 85.03 K -188.12 °C -306.616 °F | 610 K 336.85 °C 638.33 °F |
Atomic properties
| Fluorine | Astatine | |
|---|---|---|
| Electronegativity (Pauling Scale) | 3.98 | 2.2 |
| Electron affinity | 328.165 kJ/mol | 233 kJ/mol |
| Oxidation states | −1, 0 (oxidizes oxygen) | −1, +1, +3, +5, +7 () |
| Ionization energies |
|
|
Electron configuration
| Fluorine | Astatine | |
|---|---|---|
| Shorthand configuration | [He] 2s2 2p5 | [Xe] 4f14 5d10 6s2 6p5 |
| Full configuration | 1s2 2s2 2p5 | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s2 6p5 |
| Electrons per shell | 2, 7 | 2, 8, 18, 32, 18, 7 |
History
| Fluorine | Astatine | |
|---|---|---|
| Discovery | André-Marie Ampère (1810) | Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè (1940) |
| First isolation | Henri Moissan (1886) | |
| Named by | Humphry Davy, André-Marie Ampère |