# Math Help - acid base

1. ## acid base

which of the following can act as an acid and a base

CO3(2-) H2CO3 HCO3(-1) HCL

2. Using the Bronsted-Lowry theory of acids and bases:

An acid is proton donor
A base is a proton acceptor

(a proton is $\text{H}^+$. It's conventional to use the term proton in acids and bases)

$\text{CO}_3^{2-}$ happens to be the conjugate of $\text{H}_2\text{CO}_3$. Which is the acid is up to you to figure out