Question

Which among the following compounds has highest solubility in water?

• A. Phenol
• B. p-resol
• C. o-Nitrophenol
• D. p-Nitrophenol

Hint:

Smaller hydrophobic groups and free OH hydrogen bonding with water favour solubility.

Answer 1

The Correct Option is A

Step 1: Rule of thumb:
A simple structure with free hydrogen bonding groups and small hydrocarbon part dissolves best.

Step 2: Compare:
Phenol: one -OH, no extra groups. p-Cresol: extra $\text{CH}_3$, more hydrophobic. o-Nitrophenol: internal H-bond locks the OH. p-Nitrophenol: strongly associated through intermolecular H-bonds and a bulkier ring.

Step 3: Result:
Phenol is the most soluble of these four.

Final Answer:
Phenol is the most soluble, option (A). \[ \boxed{\text{Phenol (A)}} \]