Hydrofluoric Acid

Hydrofluoric Acid is a solution of hydrogen fluoride in water. Together with hydrogen fluoride, hydrofluoric acid is a valued source of fluorine, being the precursor to numerous pharmaceuticals, diverse polymers (e.g. Teflon), and most other synthetic materials that contain fluorine. Hydrofluoric acid is best known to the public for its ability to dissolve glass by reacting with SiO2, the major component of most glasses. This dissolution process can be described as follows:SiO_2(s) + 4HF(aq) → SiF_4(g) + 2H₂O_(l)SiO2(s) + 6HF(aq) → H₂[SiF₆]_(aq) + 2H2O(l)
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Noun
1. a weak poisonous liquid acid; formed by solution of hydrogen fluoride in water
(hypernym) acid

chemical formula HF, hydrofluoric acid a relatively strong acid mainly used to etch silicon dioxide. Hydrofluoric acid is commonly sold as a 49% solution and has a density of 1.17Kg/L. Fluorine is not only toxic but may be absorbed through the skin without immediate evidence of irritation and later react with the calcium in bones and or poison the person exposed to the chemical.

Eng: hydrofluoric acid
Urdu: ہائيڈرو فلورک تيزاب