Amines contain a nitrogen atom with a lone pair of electrons, which allows them to act as a base by accepting a proton. They can also act as weak acids by donating a proton from the hydrogen atoms attached to the nitrogen, although this is less common compared to their basicity.

In ethyne, each carbon atom is sp hybridized, forming a linear molecule with a bond angle of 180 degrees. The carbon atoms are connected by a triple bond consisting of one sigma bond and two pi bonds.