Final answer:
To make an alcohol more soluble in water without changing the number of carbon atoms, you can introduce more polar functional groups such as hydroxyl groups (-OH).
Step-by-step explanation:
The solubility of alcohols in water depends on the length of the carbon chain. Alcohols with one to three carbon atoms are completely soluble in water due to their ability to engage in hydrogen bonding with water molecules. However, as the chain length increases, the solubility of alcohols in water decreases because the molecules become more like hydrocarbons and less like water.
To make an alcohol more soluble in water without changing the number of carbon atoms, one option is to introduce more polar functional groups such as hydroxyl groups (-OH). These groups enhance the alcohol's ability to engage in hydrogen bonding with water. For example, if you have butanol (CH3CH2CH2CH2OH) and want to increase its solubility in water, you could add another hydroxyl group to form 1,2-butanediol (CH2OHCH2CH2CH2OH), which would have increased solubility in water due to the additional polar group.