Ka1Ka2=[H+]2[CO32-]/[H2CO3]
Well, I was trying my best avoiding this approach...but I think I should surrender
--------------------------------------BELOW IS MAINLY FOR BOREK (or other general approach lovers)-----------------------------------
Anyway, if I insist.... I guess I could try another perspective...
"It's not [CO
32-] but [H+] that is fixed; the known [CO
32-] is achieve by fixed [H+]."
Then I guess mass balance is available...
Is this correct? (My answer almost equals the one got from the net equation approach...)