Answer
a.
Acid: $H_2CO_3$
Base: $H_2O$
Conjugate Acid: $H_3O^+$
Conjugate Base: $HCO_3^-$
b.
Acid: $C_5H_5NH^+$
Base: $H_2O$
Conjugate Acid: $H_3O^+$
Conjugate Base: $C_5H_5N$
c.
Acid: $C_5H_5NH^+$
Base: $HCO_3^-$
Conjugate Acid: $H_2CO_3$
Conjugate Base: $C_5H_5N$
Work Step by Step
The acid is the substance that donates a proton and the conjugate base is the substance that accepted the proton from the acid.
Similarly, the base is the substance that receives the proton and the conjugate acid is the substance that has received a proton.
