[kanonsviel]

I know that a stronger acid corresponds to a weaker conjugate base.
But why the 3H-pyrrole(I'm not sure if it's named like this) is a weaker base than pyridine?
Is that because it is readily converted to 1H-pyrrole which is an aromatic compound, donating it's electron pair to the aromatic system?

[Schrödinger]

Yes. When one proton from the 3rd position in the pyrrole ring leaves the ring, it leaves behind a negative charge. That -ve charge will be in conjugation with the 2 other pi bonds... That would result in aromaticity...hence the acidity.

Whereas in the case of pyridine, the system is aromatic irrespective of whether the Nitrogen is protonated or not

[kanonsviel]

Got it, thanks for your help !