Chemistry - GOC Question with Solution | TestHub

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

Removing ${\mathrm{H}}_2$ gives the amidine anion :

Factor (1) atom is checked before resonance : oxygen versus nitrogen, same period, oxygen is more electronegative and holds the negative charge better. Even though the nitrogen anion is resonance-stabilised, the alkoxide wins on the atom factor, so the O-H proton ${\mathrm{H}}_1$ is more acidic.