Compare Hydrogen vs Francium
Comparing Hydrogen (H) and Francium (Fr). Atomic numbers 1 and 87 with atomic masses 1.008 u and 223 u, classified as nonmetal and alkali metal. 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
| Hydrogen | Francium | |
|---|---|---|
| Symbol | H | Fr |
| Atomic number | 1 | 87 |
| Group | 1 | 1 |
| Period | 1 | 7 |
| Block | s | s |
| Element category | Nonmetal | Alkali Metal |
Physical properties
| Hydrogen | Francium | |
|---|---|---|
| Phase at STP | Gas | Solid |
| Density | 0.08988 g/cm3 | 1.87 g/cm3 |
| Atomic weight | 1.0079 u | 223 u |
| Melting point | 13.99 K -259.16 °C -434.488 °F | 300 K 26.85 °C 80.33 °F |
| Boiling point | 20.271 K -252.879 °C -423.1822 °F | 950 K 676.85 °C 1250.33 °F |
Atomic properties
| Hydrogen | Francium | |
|---|---|---|
| Electronegativity (Pauling Scale) | 2.2 | 0.79 |
| Electron affinity | 72.769 kJ/mol | 46.89 kJ/mol |
| Oxidation states | −1, +1 (an amphoteric oxide) | +1 (a strongly basic oxide) |
| Ionization energies |
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Electron configuration
| Hydrogen | Francium | |
|---|---|---|
| Shorthand configuration | 1s1 | [Rn] 7s1 |
| Full configuration | 1s1 | 1s2 2s2 2p6 3s2 3p6 3d10 4s24p6 4d10 4f14 5s2 5p6 5d10 6s2 6p6 7s1 |
| Electrons per shell | 1 | 2, 8, 18, 32, 18, 8, 1 |
History
| Hydrogen | Francium | |
|---|---|---|
| Discovery | Henry Cavendish (1766) | Marguerite Perey (1939) |
| First isolation | Henry Cavendish (1766) | Marguerite Perey (1939) |
| Named by | Antoine Lavoisier (1783) |