Discovered by André-Marie Ampère in 1810, Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. As the most electronegative element, it is extremely reactive, as it reacts with all other elements, except for argon, neon, and helium.
It belongs to Group 17 (halogens), Period 2, p-Block. It was named after the mineral fluorite, itself named after Latin fluo (to flow, in smelting).
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