Question

How react is `SiO_2`?

Answer 1

`SiO_2` is fairly unreactive stuff.

Explanation:

There are few materials as unreactive as silicon dioxide, quartz (or sand). Unlike carbon dioxide, silicon dioxide is a non-molecular substance that features `Si-O` bonds that extend along the lattice. `SiO_2` is VERY inert (i.e. UNREACTIVE). It will react with `HF`, but that's another story.

`SiO_2(s) + 6HF(aq) rarr SiF_6^(2-) + 2H_3O^+`