Chemistry - GOC Question with Solution | TestHub

Removing ${\mathrm{H}}_1$ gives the thiophenoxide :

Removing ${\mathrm{H}}_2$ puts the negative charge on a ring carbon :

Factor (1) atom : sulphur versus carbon. Sulphur is larger and more polarisable, and holds the negative charge far better; the thiophenoxide is also resonance-stabilised into the ring. The thiophenoxide is much more stable, so the S-H proton ${\mathrm{H}}_1$ is more acidic.