Kalium

19
K
Golongan
1
Periode
4
Blok
s
Proton
Elektron
Neutron
19
19
20
Sifat Umum
Nomor atom
19
Massa atom
39,0983
Nomor massa
39
Kategori
Logam alkali
Warna
Perak
Radioaktif
Tidak
From the English word, potash - pot ashes; Latin kalium, Arab qali, alkali
Struktur kristal
Kubik Berpusat-badan
Sejarah
Potassium's symbol K comes from 'kalium' the name of the element in Germany and Scandinavia.

Potassium metal was first isolated in 1807 by Sir Humphry Davy, who derived it from caustic potash by the use of electrolysis of the molten salt with the newly discovered voltaic pile.

Potassium was the first metal that was isolated by electrolysis.
Elektron per kulit
2, 8, 8, 1
Konfigurasi elektron
[Ar] 4s1
K
People whose diets are low in potassium can suffer from hypokalemia
Sifat Fisika
Fase
Solid
Kepadatan
0,862 g/cm3
Titik lebur
336,53 K | 63,38 °C | 146,08 °F
Titik didih
1032,15 K | 759 °C | 1398,2 °F
Kalor peleburan
2,33 kJ/mol
Kalor penguapan
76,9 kJ/mol
Kapasitas kalor molar
0,757 J/g·K
Kelimpahan di kerak bumi
1,5%
Kelimpahan di alam semesta
0,0003%
Potassium
Kredit Gambar: Images-of-elements
Potassium pearls under paraffin oil
Nomor CAS
7440-09-7
PubChem CID Number
5462222
Sifat Atom
Jari-jari atom
227 pm
Jari-jari kovalen
203 pm
Elektronegativitas
0,82 (Skala Pauling)
Potensi Ionisasi
4,3407 eV
Volume atom
45,46 cm3/mol
Kondusivitas termal
1,024 W/cm·K
Bilangan oksidasi
-1, 1
Aplikasi
The greatest demand for potash has been in its use for fertilizers.

Potassium is an essential constituent for plant growth and is found in most soils.

Potassium nitrate is the main explosive ingredient in gunpowder.

Potassium hydroxide is used in the manufacture of soft soaps and as an electrolyte in alkaline batteries.
Potassium must be handled with great care with full skin and eye protection
Isotop
Isotop stabil
39K, 41K
Isotop tidak stabil
32K, 33K, 34K, 35K, 36K, 37K, 38K, 40K, 42K, 43K, 44K, 45K, 46K, 47K, 48K, 49K, 50K, 51K, 52K, 53K, 54K, 55K