H2CO3 is an acid because it gave away a proton to become HNO3~.
HNO3~ is a conjugate Base because Acids become conjugate Bases after giving away a proton.
C5H5N is a base because it accepted the proton from H2CO3 to become HC5H5N+.
HC5H5N+ is a conjugate Acid because Bases become Conjugate Acids after accepting a proton.
