C6H5COOH + NaHCO3 ---> C6H5COONa + H2O + CO2
Through, Tollen's reagent Benzaldehyde reacts with an ammoniacal solution of silver nitrate to form a silver mirror.
C6H5CHO + 2[Ag(NH3)2]+ + 3OH- --> C6H5COO- + 2Ag + 2H2O + 4NH3
However, no such reaction is given by benzoic acid.