Which ranking CORRECTLY describes the rigidity of the red bond (the central bond) shown in the figure?
A) 2 = most rigid, 3 = least rigid
B) 1 = most rigid, 5 = least rigid
C) 4 = most rigid, 3 = least rigid
D) 2 = most rigid, 1 = least rigid
E) 4 = most rigid, 1 = least rigid

Question

Which ranking CORRECTLY describes the rigidity of the red bond (the central bond) shown in the figure? 
A) 2 = most rigid, 3 = least rigid 
B) 1 = most rigid, 5 = least rigid 
C) 4 = most rigid, 3 = least rigid 
D) 2 = most rigid, 1 = least rigid 
E) 4 = most rigid, 1 = least rigid

Quizplus · Accepted Answer

The rigidity of a bond refers to its ability to rotate freely. A rigid bond is unable to rotate, while a more flexible bond is able to rotate more easily. In the given figure, the red bond is the central bond connecting two rigid cyclohexane rings. The closeness of these rings results in the bond being unable to rotate, making it the most rigid bond in the molecule. Therefore, option C correctly describes the rigidity of the bond, as it ranks the red bond as the most rigid (4) and the least rigid bond as bond 3, which is attached to an alkyl group that allows for some rotation.

Which Ranking CORRECTLY Describes the Rigidity of the Red Bond