When I have a solution of Na2SO4, the sodium sulfate should ionize:
Na2SO4(aq) -> 2Na+(aq) + SO4^{2-}(aq)
In my mind, the sodium ions should just float around, but because HSO4- is a weak acid:
HSO4- (aq) + H2O <-> H3O+ (aq) + SO4^2- (aq)
The sulfate ion should be a weak conjugate base, and hence the sodium sulfate salt should be a weak base. This was my line of reasoning, until today my friends told me it is actually a neutral salt, which was confirmed by searching online. So why is it a neutral salt? (i.e. what's wrong with my reasoning?)