Elements / 87
87Fr[223]
Francium
Alkali metal · s-block · ring Q · spoke 1
Francium is element 87, an alkali metal. It sits on ring Q (period 7) on spoke 1, the alkali metals. Follow that spoke toward the center and out again to find its chemical relatives.
Properties
| Density | 1.87 g/cm³ | Terrain → |
|---|---|---|
| Melting point | 300 K · 27 °C | Terrain → |
| Boiling point | 950 K · 677 °C | Terrain → |
| Electronegativity | 0.79 | Terrain → |
| First ionization energy | 380 kJ/mol | Terrain → |
| Atomic weight | 223 u | Terrain → |
| Crustal abundance | 1.0 × 10⁻²⁴ ppm | Terrain → |
| Discovered | 1939 | Terrain → |
Values from open reference data; see sources. "Terrain" opens that property as a 3D landscape across the whole spiral.
Two things you might not know
- Rival claimants called it virginium and moldavium. The largest lab sample ever made was just over 300,000 atoms.
- The last element discovered in nature, found by Marguerite Perey in Paris in 1939 and named after her country.
Checked against en.wikipedia.org.
Spoke 1: Alkali metals
Ring Q (period 7)
Play with Francium
Watch it fly into its seat, or raise the whole spiral into a landscape and see where it peaks.