Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six-membered ring compounds) are insoluble in water. Explain.

Question

Philoid · Accepted Answer

Glucose and sucrose are carbohydrates(optically active polyhydroxy aldehydes or ketones).

Structure of glucose:

Structure of sucrose:

As you can see both the compounds have five –OH and eight –OH groups respectively. These –OH groups are responsible for the extensive hydrogen bonding with water. This –H bonding is responsible for the solubility of glucose and sucrose in water.

In case of cyclohexane or benzene (simple six-membered ring compounds) , they do not contain any –OH groups. Hence, they cannot undergo –H bonding with water and are insoluble.