Select the incorrect statement regarding terminal alkynes.

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Understanding acidity in terminal alkynes hinges on the hydrogen attached to a carbon that is part of a carbon–carbon triple bond. That terminal hydrogen sits on an sp-hybridized carbon, which has a high s-character (50%). This stabilizes the conjugate base after deprotonation, so the C–H bond in a terminal alkyne is significantly more acidic than a typical alkane C–H bond. In practical terms, the pKa of a terminal alkyne is about 25, while alkanes are around 50. Because of this, terminal alkynes can be deprotonated by strong bases such as sodium amide to form acetylide anions.

Terminal alkynes do indeed have sp hybridization, which accounts for their linear geometry and the increased acidity. They can be deprotonated by strong bases, and they are more acidic than alkanes. The statement claiming they are not as acidic as alkanes is false for these reasons.