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Potassium (K)

Atomic number: 19 · Category: alkali metal · Group 1 · Period 4 · Phase: Solid

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.

Atomic mass: 39.09831
Density: 0.862
Melting point: 336.7 K
Boiling point: 1032 K
Appearance: silvery gray
Source: Wikipedia
Block: s
Molar heat: 29.6
CPK color:#8f40d4

Electronic structure

Electron configuration: 1s2 2s2 2p6 3s2 3p6 4s1
Configuration (semantic): [Ar] 4s1
Shells: 2, 8, 8, 1
Electronegativity (Pauling): 0.82
Electron affinity: 48.383
Ionization energies: 418.8, 3052, 4420, 5877, 7975, 9590, 11343, 14944, 16963.7, 48610, 54490, 60730, 68950, 75900, 83080, 93400, 99710, 444880, 476063

Periodic position

Group: 1
Period: 4
xpos: 1
ypos: 4

Spectral/Bohr images

Image
Potassium Pieces
3D Model