19
K
1
週期
4
s
個質子
電子
個中子
19
19
20
一般屬性
原子序數
19
標準原子質量
39.0983
品質編號
39
類別
鹼金屬
顏色
銀色
放射性
從英語單詞“ potash”開始-鍋灰; 拉丁語“鉀”,阿拉伯語“ qali”,鹼
晶體結構
Body Centered Cubic
歷史
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.
每個外殼的電子
2, 8, 8, 1
電子排布
[Ar] 4s1
K
People whose diets are low in potassium can suffer from hypokalemia
物理性質
物態
固體
密度
0.862 g/cm3
熔點
336.53 K | 63.38 °C | 146.08 °F
沸點
1032.15 K | 759 °C | 1398.2 °F
熔化熱
2.33 kJ/mol
汽化熱
76.9 kJ/mol
比熱容
0.757 J/g·K
地殼豐度
1.5%
宇宙豐度
0.0003%
Potassium
圖片來源: Images-of-elements
Potassium pearls under paraffin oil
CAS 編號
7440-09-7
Pubchem CID 編號
5462222
原子性質
原子半徑
227 pm
共價半徑
203 pm
電負性
0.82 (鲍林标度)
電離電位
4.3407 eV
原子體積
45.46 cm3/mol
熱導率
1.024 W/cm·K
氧化態
-1, 1
應用
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
同位素
穩定同位素
39K, 41K
不穩定同位素
32K, 33K, 34K, 35K, 36K, 37K, 38K, 40K, 42K, 43K, 44K, 45K, 46K, 47K, 48K, 49K, 50K, 51K, 52K, 53K, 54K, 55K