Butanal (MW= 72)has a boiling point of 76 °C while butanol (MW= 74)has a boiling point of 118 °C.What accounts for this difference in boiling points?
A)Butanol is polar while butanal is not polar.
B)Butanol can exhibit dipole-dipole interactions while butanal cannot.
C)Butanol can hydrogen bond and butanal cannot hydrogen bond.
D)Butanal is less sterically hindered than butanol.

Question

Quizplus · Accepted Answer

The difference in boiling points between butanal and butanol is due to the ability of butanol to hydrogen bond, while butanal cannot. Hydrogen bonding is a strong intermolecular force that requires the presence of a hydrogen atom bonded to an electronegative element (such as oxygen or nitrogen), which can interact with another electronegative element. Butanol has a hydroxyl (-OH) functional group that contains both a hydrogen atom and an oxygen atom, allowing it to hydrogen bond with other butanol molecules. Butanal, on the other hand, has a carbonyl group (-C=O), which does not contain any hydrogen atoms bonded to an electronegative element and cannot participate in hydrogen bonding. As a result, butanol has stronger intermolecular forces and a higher boiling point than butanal.

Butanal (MW= 72)has a Boiling Point of 76 °C While