Advanced Placement (AP) Chemistry Practice Exam

A triple bond is defined by its composition of one sigma bond and two pi bonds. The sigma bond is formed by the head-on overlap of atomic orbitals, allowing for a strong and stable bond. The two pi bonds arise from the side-to-side overlap of p orbitals. This arrangement makes triple bonds significantly stronger and shorter than single or double bonds, contributing to the overall stability of molecules that contain them.

The presence of two pi bonds adds to the bond strength, making it more difficult to break compared to a single bond or a double bond. This is crucial when considering the reactivity and stability of compounds featuring triple bonds, such as nitrogen gas (N₂) or alkynes.

In the context of the other responses, while a common misconception is that a triple bond is the longest and least energy-intensive bond, in reality, it is among the shortest and strongest due to the increased overlap of orbitals. A statement about the bond being highly unstable and easily breakable would also be misleading, as triple bonds generally exhibit strong stability in appropriate molecular contexts. Thus, the correct answer highlights the specific bonding characteristics defining a triple bond accurately.