Chemistry - GOC Question with Solution | TestHub

Removing H₁ gives the acetylide :

Removing H₂ gives the amide anion :

Nitrogen is more electronegative than carbon, but the orbital factor dominates : the acetylide lone pair sits in an sp orbital with 50% s-character, held much closer to the nucleus than the sp3 lone pair on nitrogen. The acetylide is more stable, so the terminal alkyne proton H₁ is more acidic.