Atomic symbol: F
Atomic number: 9
Atomic mass: 19.00
Appearance: Pale yellow gas at STP
Series: Halogens (Reactive nonmetals)
Electron configuration: 1s² 2s² 2p⁵
Fluorine at room temperature, F~2~, is highly toxic and extremely reactive.
Most electronegative element.
Fun Fact! Compounds of fluorine, such as sodium fluoride, are used in toothpastes, mouthwashes and in drinking water to prevent dental cavities.