Talium

81
Tl
Golongan
13
Periode
6
Blok
p
Proton
Elektron
Neutron
81
81
123
Sifat Umum
Nomor atom
81
Massa atom
204,3833
Nomor massa
204
Kategori
Logam pasca-​transisi
Warna
Perak
Radioaktif
Tidak
From Greek thallos, meanin a green shoot or twig
Struktur kristal
Segienam Sederhana
Sejarah
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.
Elektron per kulit
2, 8, 18, 32, 18, 3
Konfigurasi elektron
[Xe] 4f14 5d10 6s2 6p1
Tl
Agatha Christie made use of thallium's toxicity in her novel The Pale Horse
Sifat Fisika
Fase
Solid
Kepadatan
11,85 g/cm3
Titik lebur
577,15 K | 304 °C | 579,2 °F
Titik didih
1746,15 K | 1473 °C | 2683,4 °F
Kalor peleburan
4,2 kJ/mol
Kalor penguapan
165 kJ/mol
Kapasitas kalor molar
0,129 J/g·K
Kelimpahan di kerak bumi
0,000053%
Kelimpahan di alam semesta
5×10-8%
Pure
Kredit Gambar: Images-of-elements
Pure thallium under argon
Nomor CAS
7440-28-0
PubChem CID Number
5359464
Sifat Atom
Jari-jari atom
170 pm
Jari-jari kovalen
145 pm
Elektronegativitas
1,62 (Skala Pauling)
Potensi Ionisasi
6,1082 eV
Volume atom
17,2 cm3/mol
Kondusivitas termal
0,461 W/cm·K
Bilangan oksidasi
1, 3
Aplikasi
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
Isotop
Isotop stabil
203Tl, 205Tl
Isotop tidak stabil
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