Overview

Cobalt is a chemical element with symbol Co and atomic number 27. Like nickel, cobalt in the Earth's crust is found only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.

Electron configuration

The electron configuration of Cobalt is [Ar] 3d7 4s2, with electron shells of 2, 8, 15, 2.

Physical and chemical properties

Cobalt is classified as a transition metal. It has an atomic mass of 58.933 and exists as a solid at standard conditions, appearing as hard lustrous gray metal.

Real-world uses of Cobalt

As a transition metal, Cobalt is typically used in alloys, industrial manufacturing, electronics, or as a catalyst in chemical reactions.

Interesting facts about Cobalt

Explore Cobalt interactively

Want to compare Cobalt with other elements or see it highlighted on the full table? Open the interactive periodic table and click on Co to explore properties, trends, and neighboring elements. You can also test your knowledge with our periodic table quiz game.

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What is Cobalt used for?

As a transition metal, Cobalt is typically used in alloys, industrial manufacturing, electronics, or as a catalyst in chemical reactions.

What is the atomic number of Cobalt?

The atomic number of Cobalt is 27, meaning it has 27 protons in its nucleus.

What is the electron configuration of Cobalt?

The electron configuration of Cobalt is [Ar] 3d7 4s2.

Is Cobalt a metal, nonmetal, or metalloid?

Cobalt is classified as a transition metal.