Thallium

81
Tl
Gruppe
13
Periode
6
Block
p
Protonen
Elektronen
Neutronen
81
81
123
Generelle Eigenschaften
Ordnungszahl
81
Atommasse
204,3833
Massenzahl
204
Kategorie
Metalle
Farbe
Silber
Radioaktiv
Nein
Aus dem Griechischen thallos (grüner Zweig)
Kristallstruktur
Einfach hexagonal
Geschichte
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.
Elektronen pro Schale
2, 8, 18, 32, 18, 3
Elektronenkonfiguration
[Xe] 4f14 5d10 6s2 6p1
Tl
Agatha Christie made use of thallium's toxicity in her novel The Pale Horse
Physikalische Eigenschaften
Aggregatzustand
Fest
Dichte
11,85 g/cm3
Schmelzpunkt
577,15 K | 304 °C | 579,2 °F
Siedepunkt
1746,15 K | 1473 °C | 2683,4 °F
Schmelzwärme
4,2 kJ/mol
Verdampfungswärme
165 kJ/mol
Spezifische Wärmekapazität
0,129 J/g·K
Häufigkeit in der Erdkruste
0,000053%
Häufigkeit im Universum
5×10-8%
Pure
Danksagungen für Bilder: Images-of-elements
Pure thallium under argon
CAS-Nummer
7440-28-0
PubChem CID Number
5359464
Atomeigenschaften
Atomradius
170 pm
Kovalenter Radius
145 pm
Elektronegativität
1,62 (Pauling-Skala)
Ionisierungsenergie
6,1082 eV
Molares Volumen
17,2 cm3/mol
Wärmeleitfähigkeit
0,461 W/cm·K
Oxidationszustände
1, 3
Anwendung
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
Isotope
Stabile Isotope
203Tl, 205Tl
Instabile Isotope
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