Which of the following best explains why the C–H bond in acetylene (HC≡CH) has a…
CHEMISTRY · Single correct · AP · Chemistry · Compound Structure and Properties · Compound Structure and Properties
Problem
Which of the following best explains why the C–H bond in acetylene (HC≡CH) has a higher bond energy than the C–H bond in ethane (CH3–CH3)?
(a) The carbon in acetylene is sp2 hybridized, giving the C–H bond more s-character than in ethane and therefore greater strength.
(b) Greater steric crowding around the C–H bonds in ethane lengthens and weakens them relative to the bonds in acetylene.
(c) The carbon in acetylene is sp hybridized, giving the C–H bond greater s-character and stronger orbital overlap.
(d) The adjacent triple bond in acetylene delocalizes electron density through resonance, directly reinforcing the neighboring C–H bonds.