NaHCO3 is a basic salt.
NaHCO3(aq) (reversible) Na+ + HCO3-
HCO3- (reversible) H+ + CO3(2-)
This is unexplained by Arrhenius' definition because we know CO3(2-) acts as a base, but it does not emit an OH- when it reacts, which is what the Arrhenius definition defines as an acid.
The...