Hydrogen Fluoride

Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e.g. Teflon). HF is widely used in the petrochemical industry and a component of many superacids. HF boils just below room temperature whereas the other hydrogen halides condense at much lower temperatures. Aqueous solutions of HF, called hydrofluoric acid, are strongly corrosive.
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Noun
1. a colorless poisonous corrosive liquid made by the action of sulphuric acid on calcium fluoride; solutions in water are hydrofluoric acid
(hypernym) fluoride

chemical formula HF, hydrogen fluoride is a toxic, corrosive gas with a TLV of 3ppm. Hydrogen fluoride has a sharp irritating odor and is irritating to lungs, skin and eyes. Hydrogen bromide is used to generate hydrofluoric acid.