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Properties of Matter Element Card 7, Lesson 21



Melting point

-219° C

Boiling point

-188° C


0.0017 g/cm³


Pale yellow gas

Other physical properties


Chemical properties

Fluorine is the most reactive of all the elements. It reacts with almost all substances (even water burns in fluorine, producing a bright flame). It reacts with hydrogen to form hydrogen fluoride. When hydrogen fluoride is dissolved in water, it forms hydrofluoric acid. Fluorine is very poisonous.


Fluorine forms crystalline compounds with metals.


Compounds of fluorine are added to drinking water to reduce tooth decay. They are also used in nonstick pans and refrigerant coolants. Hydrofluoric acid is used to etch glass.


Fluorine is made by the electrolysis of two of its compounds: hydrofluoric acid and potassium fluoride.



Fluorine is a very reactive and poisonous gas, but fluorine compounds are used to make nonstick coatings on pans.


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