19 K Potassium 39,098 u

Potassium

Período
4
Grupo
1
Bloco
s-bloco
Fase (STP)
Solid

Potassium is an essential alkali metal for all living cells. It is the seventh most abundant element in Earth's crust.

Aparência: Silvery-gray

About Potassium

Essential to every living cell, potassium is a soft, silvery alkali metal that reacts vigorously with water. It has atomic number 19 and an atomic mass of 39.098, a notably large atomic radius of 243 pm, and a low melting point of 337 K. Its single valence electron ([Ar] 4s1) is loosely held, giving the low electronegativity of 0.82 and a first ionization energy of just 419 kJ/mol. Humphry Davy first isolated the metal in 1807. Potassium is the seventh most abundant element in Earth's crust, but its reactivity means it never occurs free. It belongs to group 1, period 4.

Propriedades físicas

Massa atômica 39.098 u
Densidade 0.862 g/cm³
Ponto de fusão 63.6 °C
Ponto de ebulição 758.9 °C
Fase em STP Solid
Raio atômico 243.0 pm

Propriedades eletrônicas

Eletronegatividade 0.82
Energia de ionização 418.8 eV
Afinidade eletrônica 48.4 eV
Elétrons de valência 1

Configuração eletrônica

Configuração [Ar] 4s¹

Electron Shell Configuration

Potassium electron shell configuration K 2e⁻ 8e⁻ 8e⁻ 1e⁻
Electron shell structure of Potassium — electrons per shell.
Shell Electrons
1 (K) 2
2 (L) 8
3 (M) 8
4 (N) 1

Position in Periodic Table

Potassium position in the periodic table K

Descoberta

Descoberto por: Humphry Davy
Ano: 1807

Bloco e período

Bloco

s p d f

Período

1 2 3 4 5 6 7

Tabela Periódica

Lantanídeos Actinídeos

Reações envolvendo K

Lead Iodide Precipitation (Golden Rain)

Pb(NO₃)₂ + 2KI → PbI₂↓ + 2KNO₃

Precipitation

Potassium Reacting with Water

2K + 2H₂O → 2KOH + H₂

Single Replacement

Chlorine Displacing Iodine from Potassium Iodide

Cl₂ + 2KI → 2KCl + I₂

Single Replacement

Lead Nitrate and Potassium Iodide (Golden Rain)

Pb(NO₃)₂ + 2KI → PbI₂ + 2KNO₃

Double Replacement

Thermal Decomposition of Potassium Chlorate

2KClO₃ → 2KCl + 3O₂

Decomposition
Ver as 13 reações →

Compounds Containing Potassium

Potassium Hydroxide

KOH

Potassium Nitrate

KNO₃

Potassium Chloride

KCl

Potassium Permanganate

KMnO₄

Potassium Dichromate

K₂Cr₂O₇

Potassium Iodide

KI

Potassium Carbonate

K₂CO₃

Potassium Phosphate Dibasic

K₂HPO₄

Potassium Aluminum Sulfate

KAl(SO₄)₂

Potassium Ferricyanide

K₃[Fe(CN)₆]

Potassium Ferrocyanide

K₄[Fe(CN)₆]

Potassium Persulfate

K₂S₂O₈

Mais Metal Alcalino

3 Li Lithium 11 Na Sodium 37 Rb Rubidium 55 Cs Cesium 87 Fr Francium

Frequently Asked Questions

What is Potassium?
Potassium (K) is a chemical element with atomic number 19. It is a solid at standard temperature and pressure, classified as a metal alcalino.
What are the key properties of Potassium?
Potassium has an atomic mass of 39.098 u, density of 0.862 g/cm³, melting point of 63.6°C, boiling point of 758.9°C.
What is the electron configuration of Potassium?
The electron configuration of Potassium is [Ar] 4s1. It is in the s-block of the periodic table.
Who discovered Potassium?
Potassium was discovered by Humphry Davy in 1807.
What is the electronegativity of Potassium?
Potassium has an electronegativity of 0.82 on the Pauling scale.