Potassium (K)
Kalium
Potassium (K) is an alkali metal in period 4, group 1. Its relative atomic mass is 39.098 and the molar mass of the atom is 39.098 g/mol.
Atomic number 19
Atomic mass 39.098
Molar mass 39.098 g/mol
Category Alkali metal Solid
Properties of potassium
| Atomic number | 19 |
|---|---|
| Symbol | K |
| Latin name | Kalium |
| Relative atomic mass | 39.098 |
| Molar mass | 39.098 g/mol |
| Group, period, block | 1, 4, s |
| Category | Alkali metal |
| State at 20 °C | Solid |
| Electron configuration | [Ar] 4s¹ |
| Electronegativity (Pauling) | 0.82 |
| Atomic radius | 220 pm |
Electron configuration of potassium
Electrons per shell
K2L8M8N1
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
Noble-gas notation
19 protons · 19 electrons[Ar] 4s¹
Formula and compounds of potassium
Simple substanceKpotassiumMolar mass of K: 39.098 g/mol
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Frequently asked questions
The relative atomic mass of potassium is 39.098, so the molar mass of the atom is 39.098 g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹. Noble-gas notation: [Ar] 4s¹.