Question

Which from following statements is NOT true for phenol?

• A. Phenols are polar molecules.
• B. Pure phenol is odourless, nontoxic, high melting solid.
• C. Boiling points of phenols increases with increase in molecular mass.
• D. Phenols show appreciable solubility in water.

Hint:

Phenol was famously the first surgical antiseptic (carbolic acid) introduced by Joseph Lister. Its powerful, characteristic medicinal smell is unmistakable in classic medical settings.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
We are evaluating four statements regarding the physical and chemical properties of phenol ($C_6H_5OH$) to identify the one that is factually incorrect.

Step 2: Detailed Explanation:
Let's analyze the validity of each statement:
- (a) Phenols are polar: True. The highly electronegative oxygen creates a strong dipole moment along the C-O and O-H bonds.
- (c) Boiling points increase with mass: True. As molecular mass increases, van der Waals dispersion forces increase, elevating the boiling point.
- (d) Soluble in water: True. Phenol can readily form intermolecular hydrogen bonds with water molecules, giving it appreciable solubility.
- (b) Pure phenol is odourless and nontoxic: False. Phenol possesses a very distinct, strong, and sweet "hospital" or "carbolic" odor. Furthermore, it is highly toxic and extremely corrosive to human skin, causing severe chemical burns upon contact. It is also a low-melting solid (melting point $\approx 40^\circ$C).

Step 3: Final Answer:
Statement (b) is entirely incorrect, making it the right answer.