Salancy,+Anna

Thallium, Tl

Boiling point: 1473 C, 2683.4 F, 1746.15 K.Melting point: 304 C, 579.2 F, 577.15 K.

Density @ 20oC: 11.85 g/cm3

Electrons:81 Protons:81 Neutrons in most abundant isotope:124 Atomic mass: 204.38

Atomic number:81

Electron Configuration: [Xe]6s24f145d106p1 Shell structure: 2.8.18.32.18.3 - Thallium's orbital notation is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p1.

Valence electrons:8

Thallium was discovered spectroscopically by Sir William Crookes, an English chemist, in 1861. Crooks had obtained the sludge left over from the production of sulfuric acid (H2SO4) from a friend. After removing all of the selenium from the sludge, he inspected it with a device known as a spectroscope to look for signs of tellurium. Rather than seeing the yellow spectral lines produced by tellurium, he observed a bright green line that no one had ever seen before.

quickly combines with oxygen and water vapor from the atmosphere, forming a black, powdery substance. Thallium, used in conjunction with sulfur or selenium and arsenic, forms low melting glass. Thallium sulfate (Tl2SO4), an odorless, tasteless thallium compound.

The metal is reasonably abundant in the Earth's crust at a concentration estimated to be about 0.7 part per million, it exists mostly in association with potassium minerals in clays, soils, and granites and, thus, is not generally considered to be commercially recoverable from those forms. The major source of commercial thallium is the trace amounts found in copper, lead, zinc, and other sulfide ores.

When freshly exposed to air, thallium exhibits a metallic lustre, but soon develops a blueish-grey tinge, resembling lead in appearance. A heavy oxide builds up on thallium if left in air, and in the presence of water the hydroxide is formed. The metal is very soft and malleable. It can be cut with a knife.

Thallium is most commonly used in photography, making low-melting and highly refractive glass and in treating skin infections. The element is also extensively used in the making of rodent and insect poisons, more so in rats, mice and ants poisons.

Cost, pure: $48 per 100g Cost, bulk: $ per 100g