Organic compounds that react with carbonate ions
Cook it up with ethylenediamine or diethylenetriamine- but don't bet on it.  What do you plan to have as the counterion for $\ce{K^+}$?  Check your carbon oxidation states for the second half of your question.

No, wait!  Add citric acid.  Yeah, that's the ticket.  Plop, plop, fizz, fizz.