Thallium
| Symbol | Tl |
| Atomic Number | 81 |
| Atomic Mass | 204.383 g.mol −1 |
| Discovered by | Sir William Crookes in 1861 |
Chemical Properties of Thallium
| Group | Boron | Melting point | 304 °C |
| Period | 6 | Boiling point | 1473 °C |
| Block | 13 | Density (g cm−3) | 11.71 g.cm−3 at 20°C |
| Atomic number | 81 | Relative atomic mass | 204.383 g.mol -1 |
| State at 20°C | Solid | Key isotopes | 205Tl |
| Electron configuration | [Xe] 4f14 5d10 6s2 6p1 | CAS number | 7440-28-0 |
| ChemSpider ID | 4514293 | ChemSpider is a free chemical structure database | |
What is Thallium?
- Thallium (Tl) with an atomic number of 81 is found in the periodic table with the symbol.
- Thallium is not freely found in nature. It is a soft gray post-transition metal. It resembles tin when isolated but when exposed to air it may discolor.
- There are around eighty-one electrons present in the atom of thallium with an electronic configuration of [Xe] 4f14 5d10 6s2 6p1.
- This element can be generated artificially. It can be obtained by smelting of lead and zinc. It is generally obtained as a by-product in the production of sulphuric acid.
Uses of Thallium
- In ancient times it was used as a rat poison and as an ant killer.
- Thallium compounds are used in the manufacture of glasses.
- It is used in photocells.
- It is used in the production of infrared optics.
Properties of Thallium
- Thallium melts easily.
- Thallium Salts that are soluble are generally toxic. They are merely tasteless.
- It oxidizes at +3 and +1 oxidation states forming ionic salts.
- There are several thallium compounds wherein Thallium(III) resembles the aluminum (III) compounds.
Certain Facts About Thallium
- It was named after Greek word thallus which means twig.
- Thallium is suspected to be carcinogenic. Hence direct contact should be avoided with the skin.
Practise This Question
