[Susan]

Susan asked the Naked Scientists:
   
Why won't most acids corrode glass containers?

What do you think?

[lightarrow]

Because those which do corrode glass, as HF, are toxic and make toxic gases in the reaction, so are not used.
About the other strong acids, as HCl, H₂SO₄ ecc. they don't attack glass, even if it is essentially an oxide, that is silicon dioxide, because this is a covalent compound with strong bonds and because the resultant Si⁴⁺ ion of the hypotetical reaction is a too strong lewis acid to form in presence of water, so it would immediately react with the water formed, re-generating the initial acid and the silicon dioxide.

IF this reaction happened:

4H⁺ + SiO₂ → 2H₂O + Si⁴⁺,

then immediately the reverse would happen:

2H₂O + Si⁴⁺ → 4H⁺ + SiO₂
and this would be much more favourite.

In conclusion, the equilibrium:

4H⁺ + SiO₂ ↔ 2H₂O + Si⁴⁺

is strongly displaced to the left.

HF acts with a different mechanism, because it forms SiF₄ and H₂SiF₆ which are stable, covalent compounds, so no Si⁴⁺ ions are formed.
http://en.wikipedia.org/wiki/Hydrofluoric_acid