Thallium element (Tl) is in group 13 and period 6 of a periodic table. Thallium is in the p-block and it is classified as a post-transition element on the periodic table.
There is a lot more information related to thallium which is mentioned in the Information Table given below.
So let’s dive right into it!
Table of contents
- Thallium element (Information Table)
- Thallium element in Periodic table
- Facts about Thallium
- Properties of Thallium
- Uses of Thallium
Thallium Element (Information Table)
The important data related to thallium element is given in the table below.
|Appearance of thallium||Silvery gray appearance|
|Atomic number of thallium||81|
|Symbol of thallium||Tl|
|Atomic mass of thallium||204.38 u|
|Protons, Neutrons & Electrons in thallium||Protons: 81, Neutrons: 123, Electrons: 81|
|State of thallium (at STP)||Solid|
|Group number of thallium in periodic table||13|
|Period number of thallium in periodic table||6|
|Block of thallium in periodic table||p-block|
|Category of thallium||Post transition element (boron group)|
|Bohr model or Electrons per shell or Electrons arrangement in thallium||2, 8, 18, 32, 18, 3|
|Electron configuration of thallium||[Xe] 4f14 5d10 6s2 6p1|
|Orbital diagram of thallium|
|Valence electrons in thallium||3|
|Electronegativity of thallium (on pauling scale)||1.62|
|Atomic radius of thallium (van der Waals radius)||196 picometers|
|Density of thallium||11.85 g/cm3|
|1st ionization energy of thallium||6.108 eV|
|Main isotope of thallium||205Tl|
|Melting point of thallium||577 K or 304 °C or 579 °F|
|Boiling point of thallium||1746 K or 1473 °C or 2683 °F|
|Crystal structure of thallium||Hexagonal Close Packed (HCP)|
|Discovery of thallium||By William Crookes (in 1861)|
Also see: Interactive Periodic Table (It has rotating bohr models as well as many other details of all the 118 elements in a single periodic table).
Thallium element in Periodic table
The Thallium element (Tl) has the atomic number 81 and is located in group 13 and period 6. Thallium is a metal and it is classified as a post-transition element.
Facts about thallium
Here are a few interesting facts about thallium.
- William Crookes discovered thallium in the year 1861.
- Thallium was given its name from the Greek word “thallos”, meaning green shoot.
- The earth’s crust contains around 850 parts per billion (by weight) of thallium.
- Around 70% of the total thallium is used in the electronics industries.
- Thallium is stored in mineral oil because of its reactivity.
Properties of thallium
Here is a list of some physical properties and chemical properties of thallium.
Physical properties of thallium
- Thallium has a silvery gray appearance.
- Thallium is soft metal and it can be cut with a knife too.
- The density of thallium is 11.85 g/cm3 and its atomic mass is 204.38 amu.
- The melting point and boiling point of thallium is 577 K and 1746 K respectively.
- Thallium has HCP crystal structure.
- Thallium has many isotopes, and the most abundant isotope is 205Tl.
Chemical properties of thallium
- Thallium easily reacts with the atmospheric oxygen and tarnishes, if kept open in the air.
- Thallium reacts with water and forms a thallium hydroxide.
- Thallium has an electronegativity of 1.62 on the pauling scale.
Uses of thallium
Here are some uses of the thallium element.
- Thallium oxide is used in making glasses that require a higher refractive index.
- Thallium is also used in electronic industries (specially in the semiconductor material used for selenium rectifiers).
- Thallium sulfide is a compound of thallium which is used in photocells.