Thallium (Tl) — Element Properties, Uses & Facts
Overview
Thallium is a chemical element with symbol Tl and atomic number 81. This soft gray post-transition metal is not found free in nature. When isolated, it resembles tin, but discolors when exposed to air.
Electron configuration
The electron configuration of Thallium is [Xe] 4f14 5d10 6s2 6p1, with electron shells of 2, 8, 18, 32, 18, 3.
Physical and chemical properties
Thallium is classified as a transition metal. It has an atomic mass of 204.38 and exists as a solid at standard conditions, appearing as silvery white.
Real-world uses of Thallium
As a transition metal, Thallium is typically used in alloys, industrial manufacturing, electronics, or as a catalyst in chemical reactions.
Interesting facts about Thallium
- Thallium has the atomic number 81 and chemical symbol Tl.
- It belongs to period 6, group 13 of the periodic table.
- Thallium was discovered by William Crookes.
Explore Thallium interactively
Want to compare Thallium with other elements or see it highlighted on the full table? Open the interactive periodic table and click on Tl to explore properties, trends, and neighboring elements. You can also test your knowledge with our periodic table quiz game.
What is Thallium used for?
As a transition metal, Thallium is typically used in alloys, industrial manufacturing, electronics, or as a catalyst in chemical reactions.
What is the atomic number of Thallium?
The atomic number of Thallium is 81, meaning it has 81 protons in its nucleus.
What is the electron configuration of Thallium?
The electron configuration of Thallium is [Xe] 4f14 5d10 6s2 6p1.
Is Thallium a metal, nonmetal, or metalloid?
Thallium is classified as a transition metal.