The Element Thallium

• Atomic Number 81 Thallium
• What Has An Atomic Number Of 81
• Bromine Atomic Number 81

Atomic Number 81 Thallium

[Click for Isotope Data]

Atomic number 81 - a soft grey malleable metallic element that resembles tin but discolors on exposure to air; it is highly toxic and is used in rodent and insect poisons; occurs in zinc blende and some iron ores. Atomic Number: 81 Atomic Mass: 204.3833 amu Melting Point: 303.5 °C (576.65 K, 578.3 °F) Boiling Point: 1457.0 °C (1730.15 K, 2654.6 °F) Number of Protons/Electrons: 81 Number of Neutrons: 123 Classification: Other Metals Crystal Structure: Hexagonal Density @ 293 K: 11.85 g/cm 3 Color: bluish Atomic Structure. Regarding this, how many protons neutrons and electrons are present in a single atom of bromine − 81? Bromine (Br), at atomic number 35, has a greater variety of isotopes. The atomic mass of bromine (Br) is 79.90. There are two main isotopes at 79 and 81, which average out to the 79.90amu value. The 79 has 44 neutrons and the 81 has 46 neutrons.

Atomic Number: 81

Atomic Weight: 204.3833

Melting Point: 577 K (304°C or 579°F)

Boiling Point: 1746 K (1473°C or 2683°F)

Density: 11.8 grams per cubic centimeter

Phase at Room Temperature: Solid

Element Classification: Metal

Period Number: 6

Group Number: 13

Group Name: none

What's in a name? From the Greek word for a green shoot or twig, thallos.

Say what? Thallium is pronounced as THAL-ee-em.

History and Uses:

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. He named the new element that was producing the green line thallium, after the greek word for 'green twig', thallos. He isolated samples of thallium the next year. Thallium is found in the minerals crooksite (CuThSe), lorandite (TlAsS₂) and hutchinsonite ((Pb, Tl)₂As₅S₉), but is usually obtained as a byproduct of the production of sulfuric acid or as a byproduct of refining zinc or lead.

There are no uses for metallic thallium since pure thallium 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, was once used as a rat and ant poison, although it has been banned from household use in the United States since 1974. Thallium sulfide (Tl₂S), thallium iodide (TlI) and thallium bromide (TlBr) are all compounds used in devices to detect infrared radiation.

Estimated Crustal Abundance: 8.5×10^-1 milligrams per kilogram

Estimated Oceanic Abundance: 1.9×10^-5 milligrams per liter

Number of Stable Isotopes: 2 (View all isotope data)

Ionization Energy: 6.108 eV

Oxidation States: +3, +1

What Has An Atomic Number Of 81

Bromine Atomic Number 81

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