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Fluorine (F)

Element with atomic number 9, category: Halogen, a gas at room temperature.

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Element 9 of 118

Halogen

F

Fluorine

Group 17, Period 2

Atomic Number
9
Atomic Mass
18.998 u
State at Room Temperature
Gas

Common Uses

Toothpaste, Teflon

Electron Diagram

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About Fluorine

Fluorine is a chemical element with the symbol F and atomic number 9, meaning every atom has 9 protons in its nucleus. It is classed as Halogen and is a gas at room temperature. Its atomic mass is about 18.998 atomic mass units (u).

On the periodic table, Fluorine sits in group 17, period 2, which determines how many electron shells it has and how it tends to react with other elements.

Uses of Fluorine

In daily life and industry, Fluorine is used for Toothpaste, Teflon. These uses are closely tied to the typical properties of elements in the Halogen category.

Electron Structure of Fluorine

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), Fluorine has 2 electron shells, with an approximate arrangement of 2, 7 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.

Frequently Asked Questions

The chemical symbol of Fluorine is F, with atomic number 9 and an atomic mass of about 18.998 u.
Fluorine is in the Halogen category and is a gas at room temperature.
Fluorine is in group 17, period 2 of the periodic table.
Fluorine is commonly used for Toothpaste, Teflon.
Using the simplified Bohr model, Fluorine has 2 electron shells, with an approximate arrangement of 2, 7 electrons from the innermost shell to the outermost.