Question

What is the conjugate base of `HCO_3^-`?

Answer 1

Add a proton, and we get.........

Explanation:

`HCO_3^(-) + H^(+) rarr H_2CO_3(aq)`

`"Carbonic acid,"` `H_2CO_3`. As far as anyone knows, `"carbonic acid"` is hydrated, i.e. dissolved, carbon dioxide, i.e. `H_2O*CO_2`.

All I have done here is to conserve both mass and charge.