Menu
Other Resources

Compare Potassium vs Lithium

Comparing Potassium (K) and Lithium (Li). Atomic numbers 19 and 3 with atomic masses 39.098 u and 6.938 u, classified as alkali metal 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.

vs
K
Potassium
#19
Li
Lithium
#3

Periodic properties of the elements

PotassiumLithium
SymbolKLi
Atomic number193
Group11
Period42
Blockss
Element categoryAlkali MetalAlkali Metal

Physical properties

PotassiumLithium
Phase at STPSolidSolid
Density0.862 g/cm30.534 g/cm3
Atomic weight39.0983 u6.938 u
Melting point336.7 K
63.55 °C
146.39 °F		453.65 K
180.5 °C
356.9 °F
Boiling point1032 K
758.85 °C
1397.93 °F		1603 K
1329.85 °C
2425.73 °F

Atomic properties

PotassiumLithium
Electronegativity (Pauling Scale)0.820.98
Electron affinity48.383 kJ/mol59.6326 kJ/mol
Oxidation states−1, +1
(a strongly basic oxide)		+1
(a strongly basic oxide)
Ionization energies
  1. 418.8 kJ/mol
  2. 3052 kJ/mol
  3. 4420 kJ/mol
  4. 5877 kJ/mol
  5. 7975 kJ/mol
  6. 9590 kJ/mol
  7. 11343 kJ/mol
  8. 14944 kJ/mol
  9. 16963.7 kJ/mol
  10. 48610 kJ/mol
  11. 54490 kJ/mol
  12. 60730 kJ/mol
  13. 68950 kJ/mol
  14. 75900 kJ/mol
  15. 83080 kJ/mol
  16. 93400 kJ/mol
  17. 99710 kJ/mol
  18. 444880 kJ/mol
  19. 476063 kJ/mol
  1. 520.2 kJ/mol
  2. 7298.1 kJ/mol
  3. 11815 kJ/mol

Electron configuration

PotassiumLithium
Shorthand configuration[Ar] 4s1 [He] 2s1
Full configuration1s2 2s2 2p6 3s2 3p6 4s1 1s2 2s1
Electrons per shell2, 8, 8, 12, 1

History

PotassiumLithium
DiscoveryHumphry Davy (1807)Johan August Arfwedson (1817)
First isolationHumphry Davy (1807)William Thomas Brande, Sir Humphrey Davy (1821)
Compare Potassium with
Compare Lithium with