Can silicon dioxide dissolve in hydrofluoric acid?
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Can silicon dioxide dissolve in hydrofluoric acid?
Sure, hydrofluoric acid and hydrogen fluoride can strongly corrode silica and glass, and they can also react with elemental silicon.
What products are formed when it reacts with hydrofluoric acid? Thank you!
Under normal temperature conditions, it can form silicon tetrafluoride and water.
Under normal conditions, hydrogen fluoride reacts with silicon dioxide to produce the volatile compound silicon tetrafluoride; if the acidity is not high and there are appropriate amounts of other metal ions in the water, some fluorosilicate ions will be formed.
Hydrofluoric acid is a medium-strength acid that does not ionize completely in solution. Theoretically, it should react with silicon dioxide to produce gaseous silicon tetrafluoride and water; however, gaseous silicon tetrafluoride reacts with water to form viscous orthosilicic acid and hydrofluoric acid. Additionally, liquid silicon tetrafluoride reacts with hydrofluoric acid to yield fluorosilicic acid. As a result, the reaction proceeds slowly, and the acid becomes a mixture containing hydrofluoric acid, fluorosilicic acid, as well as an insoluble portion of orthosilicic acid.
The acid used for etching glass is hydrofluoric acid, and the reaction produces silicon tetrafluoride gas; therefore, enamel must absolutely not be used in the hydrofluoric acid industry