Here's why:

* Location on the Periodic Table: Fluorine is located in Group 17 (also known as the halogens) of the periodic table. Halogens are all non-metals.

* Physical Properties: Fluorine is a pale yellow, highly reactive gas at room temperature. Non-metals are generally gases, liquids, or brittle solids at room temperature.

* Chemical Properties: Fluorine is highly electronegative, meaning it readily gains electrons to form negative ions. Non-metals tend to gain electrons in chemical reactions.

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