Identify the conjugate base in the following reaction.

H2O (l) + HCO31- (aq) �¨ H3O+ (aq) + CO32- (aq)?

Identify the Bronsted-Lowry acid in the following reaction.

H2O (l) + HCO31- (aq) �¨ H3O+ (aq) + CO32- (aq)

1 answer

Just remember the definition.
An acid is a proton donor; a base is a proton acceptor. What does all of that mean? Look for the one on the left with more H than the one on the right with fewer H. More H means acid; fewer H means conjugate base. Crazy talk. The acid is HCO3^- and the conjugate base is CO3^2-. It should be obvious to you that the pair is HCO3^-/CO3^2-. So the one with more H is HCO3^- and that is the acid of the pair; CO3^2- is the one with fewer H so it is the conjugate base.

The other pair obviously is H2O/H3O^+. Same thing. H2O must be the base (fewer H) and H3O^+ must be the conjugate acid (more H).