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Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water. It is a precursor to almost all fluorine compounds, including pharmaceuticals such as fluoxetine (Prozac), diverse materials such as PTFE (Teflon), and elemental fluorine itself.
H 1529 (OTTO) Hydrofluoric acid, 40% Cas 7664-39-3 - used as a pickling agent to remove oxides and other impurities from stainless and carbon steels because of its limited ability to dissolve steel.