| Potassium | |
| Electrons per shell | 2,8,8,1 |
| Electron Configuration | [Ar] 4s1 ![]() |
| Ground state | 2S1/2 |
| Atomic Volume | 45.46 cm3 mol-1 |
| Electronegativity | 0.82 |
| Magnetic ordering | No data |
| Mass magnetic susceptibility | 6.7 x 10-9 |
| Molar magnetic susceptibility | 2.62 x 10-10 |
| Speed of sound | 2000 m s-1 |
Thermal Properties |
|
| Enthalpy of Atomization | 89.5 kJ mol-1 @25°C |
| Enthalpy of Fusion | 2.40 kJ mol-1 |
| Enthalpy of Vaporisation | 79.1 kJ mol-1 |
| Heat Capacity | 29.600 J mol-1 K-1 |
| Thermal Conductivity | 102.5 W m-1 K-1 |
| Thermal Expansion | 83.3 μm m-1 K-1 |
| Critcal Temperature | 2223 K (1950°C) |
| Critcal Pressure | No data. |
| Adiabatic index | No data. |
Hardness |
|
| Brinell hardness | 0.363 MPa |
| Mohs hardness | 0.4 |
Elastic Properties |
|
| Bulk modulus | 3.1 GPa |
| Shear modulus | 1.3 GPa |
Electrical Properties |
|
| Electrical resistivity | 7 x 10-8 Ω m |
| Electrical conductivity | 0.139 106/cm Ω |
Chemical Properties |
|
| Electrochemical Equivalent | 1.4587 g Ah-1 |
| Electron Work Function | 2.3 eV |
| Valence Electron Potential (-eV) | 10.4 |
| Ionization Potential | |
| 4.341 | |
| 31.625 | |
| 45.72 | |
Energy Levels |
|
| 3.3138 KeV | |
| 3.3111 KeV | |
| 3.5896 KeV | |
| 0.2591 KeV | |
| 0.262 KeV | |
| 0.2591 KeV | |
Atomic Radii |
|
| 220 pm | |
| 243 pm | |
| 196 pm | |
| 275 pm | |
| No data. | |
| 227 pm | |
Ionic Radii (Å) |
||||
| Charge | Coordination | Crystal | Ionic | Key |
| 1 | IV | 1.51 | 1.37 | |
| VI | 1.52 | 1.38 | ||
| VII | 1.6 | 1.46 | ||
| VIII | 1.65 | 1.51 | ||
| IX | 1.69 | 1.55 | ||
| X | 1.73 | 1.59 | ||
| XII | 1.78 | 1.64 | ||
| R, From r3 vs V plots. |
| C, Calculated from bond length - bond strength equations. |
| E, Estimated. |
| *, Most Reliable. |
| M, From Metallic Oxides. |
| A, Ahrens (1952) Ionic radius. |
| P, Pauling's (1960) Crystal Radius. |
Oxidation States |
|
| K+1 | |
| K-1 (in liquid NH3) | |
Ionisation Energies (kJ mol-1) ![]() |
|
| 418.8 | |
| 3051.4 | |
| 4411 | |
| 5877 | |
| 7975 | |
| 9649 | |
| 11343 | |
| 11942 | |
| 16964 | |
| 48575 | |
Crystal Structure |
|
| Body centred cubic | |
![]() |
a = 532.8 pm |
| b = 532.8 pm | |
| c = 532.8 pm | |
| α = 90° | |
| β = 90° | |
| γ = 90° | |