87
Fr
223
Francium (Fr)
Element 87 · Period 7 · Group 1
alkali-metal
solid at room temp
s-block
radioactive
About Francium
Most unstable naturally occurring element. Extremely rare. Most electropositive known element.
Physical Properties
Atomic Mass
223 u
State at 25°C
Solid
Melting Point
27 °C
Boiling Point
677 °C
Density
1.87 g/cm³
Magnetism
Paramagnetic
Atomic Properties
Electron Configuration
[Rn] 7s¹
Electron Shells
2, 8, 18, 32, 18, 8, 1
Electronegativity
0.7
Atomic Radius
348 pm
Ionization Energy
380 kJ/mol
Oxidation States
+1
Discovery & History
Discovered By
Marguerite Perey
Discovery Year
1939
Named By
Marguerite Perey
Name origin: France
Frequently Asked Questions
- Is Francium a metal, nonmetal, or metalloid?
- Francium is classified as a alkali-metal.
- What state is Francium in at room temperature?
- Francium is a solid at standard room temperature (25°C).
- What is the atomic mass of Francium?
- Francium has an atomic mass of 223 atomic mass units (u).
- Who discovered Francium?
- Francium was discovered by Marguerite Perey in 1939.
- Where is Francium on the periodic table?
- Francium is element number 87, located in period 7 and group 1.