Why does corrosive acid not melt its container?

Corrosive ability depends on the type of acid and different acids are capable of dissolving or melting different materials.

By Len Fisher

Asked by: Christopher Watts, Liverpool

Corrosive’ is a relative term. Hydrofluoric acid, for example, is very corrosive towards glass, but it will not attack the plastic bottles in which it is kept. Fluorine gas attacks just about everything, but it can still be kept in copper vessels, because in attacking the copper it produces a layer of copper fluoride that blocks further attack.

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