Answer:
The hydroxyl group and aldehyde group
The form polar bonds
Step-by-step explanation:
Glucose has a very high melting point compared to cyclohexane. What could the secret be?
We now turn our attention to the structure of the both molecules. While cyclohexane is just an alkane, glucose contains both the -OH and the CHO groups which form polar bonds.
In cyclohexane, the only intermolecular force is the London dispersion forces while the intermolecular forces in glucose include the London dispersion forces as well as dipole interactions occasioned by the presence of polar -OH and -CHO groups in the molecule thereby increasing the melting point of glucose far above that of cyclohexane.