Rank the indicted C-C bonds in increasing order of bond length (shortest to longest)

Question

Quizplus · Accepted Answer

According to the concept of bond length and bond order, the bond length is inversely proportional to the bond order. As the number of pi bonds increases, the bond order increases and the bond length decreases. Here, the given structures have the same sigma bond between the carbon atoms and differ only in the number of pi bonds. Thus, the decreasing order of bond length will be I (single bond) < II (double bond) < III (triple bond). So, the correct answer is option C, I<II<III.

Rank the Indicted C-C Bonds in Increasing Order of Bond