81
Tl
13
週期
6
p
個質子
電子
個中子
81
81
123
一般屬性
原子序數
81
標準原子質量
204.3833
品質編號
204
類別
弱金屬
顏色
銀色
放射性
From Greek thallos, meanin a green shoot or twig
晶體結構
簡單六角形
歷史
Thallium was discovered spectroscopically by Sir William Crookes in 1861, in London.

In 1862, Claude-Auguste Lamy used a spectrometer to determine the composition of a selenium-containing substance which was deposited during the production of sulfuric acid from pyrite.

He noticed the new green line in the spectra and concluded that a new element was present.
每個外殼的電子
2, 8, 18, 32, 18, 3
電子排布
[Xe] 4f14 5d10 6s2 6p1
Tl
Agatha Christie made use of thallium's toxicity in her novel The Pale Horse
物理性質
物態
固體
密度
11.85 g/cm3
熔點
577.15 K | 304 °C | 579.2 °F
沸點
1746.15 K | 1473 °C | 2683.4 °F
熔化熱
4.2 kJ/mol
汽化熱
165 kJ/mol
比熱容
0.129 J/g·K
地殼豐度
0.000053%
宇宙豐度
5×10-8%
Pure
圖片來源: Images-of-elements
Pure thallium under argon
CAS 編號
7440-28-0
Pubchem CID 編號
5359464
原子性質
原子半徑
170 pm
共價半徑
145 pm
電負性
1.62 (鲍林标度)
電離電位
6.1082 eV
原子體積
17.2 cm3/mol
熱導率
0.461 W/cm·K
氧化態
1, 3
應用
Thallium selenide has been used in a bolometer for infrared detection.

Thallium is also used in gamma radiation detection equipment.

Thallium oxide has been used to produce glasses with a high index of refraction, and is used in the manufacture of photo cells.

Some of the electrodes in dissolved oxygen analyzers contain thallium.
Thallium and its compounds are highly toxic
同位素
穩定同位素
203Tl, 205Tl
不穩定同位素
176Tl, 177Tl, 178Tl, 179Tl, 180Tl, 181Tl, 182Tl, 183Tl, 184Tl, 185Tl, 186Tl, 187Tl, 188Tl, 189Tl, 190Tl, 191Tl, 192Tl, 193Tl, 194Tl, 195Tl, 196Tl, 197Tl, 198Tl, 199Tl, 200Tl, 201Tl, 202Tl, 204Tl, 206Tl, 207Tl, 208Tl, 209Tl, 210Tl, 211Tl, 212Tl