19 K 39.098
Potassium
alkali metal
Properties
- Atomic number
- 19
- Atomic mass
- 39.098 u
- Category
- alkali metal
- Group
- 1
- Period
- 4
- Block
- s-block
- State (room temp)
- Solid
- Outer-shell electrons
- 1
- Electronegativity
- 0.82 (Pauling)
- Density
- 0.862 g/cm³
- Melting point
- 63.55 °C
- Boiling point
- 758.85 °C
Electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
Noble-gas shorthand: [Ar] 4s¹
Electrons per shell: 2, 8, 8, 1 — that's 1 in the outermost shell.
About Potassium
Potassium is a chemical element with symbol K (derived from Neo-Latin, kalium) and atomic number 19. It was first isolated from potash, the ashes of plants, from which its name is derived. In the Periodic table, potassium is one of seven elements in column (group) 1 (alkali metals):they all have a single valence electron in their outer electron shell, which they readily give up to create an atom with a positive charge - a cation, and combine with anions to form salts.
- Discovered by Humphry Davy
- Appearance: silvery gray
Position in the periodic table
Data compiled from Wikipedia, PubChem, and IUPAC. Source.