,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
The bond angle varies depending on the type of bond between carbon atoms. For a single bond, its type is the sp³ hybridization. For this type, the bond angle between the carbon atoms is 109.5°. For sp² hybridization (double bonds), the bond angle is 120°. For sp hybridization (triple bonds), the bond angle is 180°. Thus,
A. This is an alcohol which consists of single bonds. So, the angle is 109.5°.
B. The angle is 180° because of the triple bond.
C. H₂C=C=CH₂ consist of a double bond, so the angle is 120°