My textbook (Facer, A2 Chemistry - used for UK EdExcel specification) states on page 36 that Silicon Dioxide is a weakly acidic oxide because of the following reaction
+ 2NaOH <> Na2
O (where <> represents the symbol "reversible")
Now, OK, I can see that the reaction is silicon dioxide plus an alkali gives water and a compound (sodium silicate?) that looks "salt-like"
However, everything I have read to date about acids (ignoring Lewis) states an acid is a proton donor.
My problem: where is the H+
? Because there isn't an H+
, how can SiO2
be an acid - even if its reaction with an alkali generates a salt ?
Salts, acids, bases