Argon (Ar)

About Argon

Argon is a chemical element with the symbol Ar and atomic number 18, meaning every atom has 18 protons in its nucleus. It is classed as Noble gas and is a gas at room temperature. Its atomic mass is about 39.948 atomic mass units (u).

On the periodic table, Argon sits in group 18, period 3, which determines how many electron shells it has and how it tends to react with other elements.

Uses of Argon

In daily life and industry, Argon is used for Light bulb filling, welding. These uses are closely tied to the typical properties of elements in the Noble gas category.

Electron Structure of Argon

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), Argon has 3 electron shells, with an approximate arrangement of 2, 8, 8 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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