What substances can exist in 20% hydrofluoric acid? Is it possible for colloids to exist?

Hydrofluoric acid can dissolve oxides and is sensitive to silicon-containing compounds. As for what substances can exist in 20% hydrofluoric acid, I think there are quite a few of them; for example, hydrocarbons can be present； As for whether colloids may exist, I believe that a colloid is a dispersion system in which the diameter of the dispersed particles ranges from 1 nm to 100 nm. Moreover, a sol is a special state of existence for a substance, rather than a distinct substance in itself; it is not an inherent property of the substance. Any substance can exist in a crystalline form under certain conditions, while existing in a colloidal form under other conditions. For example, sodium chloride is a typical crystal; it dissolves in water to form a true solution. If it is dispersed in benzene or ether using appropriate methods, a colloidal solution is formed. I think colloids may exist; it’s just that the conditions need to be explored gradually.

What substances can exist in 20% hydrofluoric acid? Substances all exist; it depends on what form of existence they are in

Hydrofluoric acid is highly toxic and corrosive; it is mainly used in the smelting of aluminum and uranium, glass etching, and pickling processes, but polytetrafluoroethylene is not affected by it. As for the other 80% of those 20%, it’s of course the presence of water. ;P