[thawksworth]

Hello!

  I’m currently in AP chemistry doing an equilibrium lab and have a quick question about polyprotic acids. I know in terms of dissociation, they can only donate one proton at a time. Ie H₂SO₄ + water -> HSO₄- + H3O⁺

However, let’s say you’re given a salt like Al2(SO4)3
Would it’s parent acid be HSO4- or H2SO4?
Because I’ve seen people say it’s H2SO4 but the salt when you mix carbonic acid and NaOH is NaHCO3.... do different polyprotic acids behave different then?

[Borek]

Depends on how nitpicky you want to be and how strong the acid is. Technically you are right that HSO₄^- is the right answer.