Cobalt (Co)

About Cobalt

Cobalt is a chemical element with the symbol Co and atomic number 27, meaning every atom has 27 protons in its nucleus. It is classed as Transition metal and is a solid at room temperature. Its atomic mass is about 58.933 atomic mass units (u).

On the periodic table, Cobalt sits in group 9, period 4, which determines how many electron shells it has and how it tends to react with other elements.

Uses of Cobalt

In daily life and industry, Cobalt is used for Batteries, magnets. These uses are closely tied to the typical properties of elements in the Transition metal category.

Electron Structure of Cobalt

Using a simplified electron shell model (at most 2 electrons in the first shell, 8 in the second, 18 in the third, and so on), Cobalt has 3 electron shells, with an approximate arrangement of 2, 8, 17 electrons from the innermost shell to the outermost. This is a simplified learning model, not the full electron configuration that accounts for the s, p, d and f subshells.

Explore Other Elements

Want to see another element or try the element symbol quiz? Go back to the Interactive Periodic Table to explore all 118 chemical elements.

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