Hydrofluoric acid, its chemical formula is $HF $. Hydrofluoric acid is an aqueous solution of hydrogen fluoride gas and is highly corrosive. Hydrofluoric acid is widely used in many fields of chemical industry.

It has unique chemical properties and can react with many metals, metal oxides and some non-metals. If it reacts with silica, this reaction is of great significance in the glass etching process: $SiO_ {2} + 4HF = SiF_ {4}\ uparrow + 2H_ {2} O $.

Due to its strong corrosiveness, strict safety procedures must be followed when using it. Operators need to wear professional protective equipment, such as chemical protective clothing, protective gloves and protective masks, to prevent hydrofluoric acid from contacting the skin and respiratory tract. In case of accidental contact, rinse with plenty of water immediately and seek medical attention promptly. Storage of hydrofluoric acid should also be cautious. It should be stored in a special corrosion-resistant container in a cool, ventilated place, away from fire and heat sources.