Which of the given statement is not correct

Options

A. Phenol is more acidic than acetic acid
B. Ethanol is less acidic than phenol
C. Ethanol has lower boiling point than ethane
D. Ethyne is a non - linear molecule

Answer

To determine which of the given statements is not correct, we will analyze each option step by step.

### Step 1: Analyze Option A
**Statement:** Phenol is more acidic than acetic acid.

- **Phenol Structure:** C6H5OH
- **Acetic Acid Structure:** CH3COOH

**Acidity Comparison:**
- To compare acidity, we look at the stability of the conjugate bases formed after deprotonation.
- The conjugate base of phenol (phenoxide ion) is stabilized by resonance across the aromatic ring.
- The conjugate base of acetic acid (acetate ion) is also stabilized by resonance, but the negative charge is localized on the oxygen atom.
- However, the resonance stabilization in phenoxide is less effective compared to acetate because the negative charge in acetate is more stable due to the electronegativity of the carbonyl group.

**Conclusion for A:** Acetic acid is more acidic than phenol. Thus, **Option A is incorrect.**

### Step 2: Analyze Option B
**Statement:** Ethanol is less acidic than phenol.

- **Ethanol Structure:** C2H5OH
- **Phenol Structure:** C6H5OH

**Acidity Comparison:**
- The conjugate base of ethanol (ethoxide ion) is less stable than the conjugate base of phenol (phenoxide ion).
- The negative charge in phenoxide is delocalized over the aromatic ring, providing greater stability compared to the ethoxide ion, which does not have such resonance stabilization.

**Conclusion for B:** Phenol is more acidic than ethanol. Thus, **Option B is correct.**

### Step 3: Analyze Option C
**Statement:** Ethane has a lower boiling point than ethanol.

- **Ethane Structure:** C2H6
- **Ethanol Structure:** C2H5OH

**Boiling Point Comparison:**
- Ethanol can form hydrogen bonds due to the presence of the hydroxyl (-OH) group, leading to higher boiling points.
- Ethane, being a non-polar molecule, cannot form hydrogen bonds and has a lower boiling point.

**Conclusion for C:** Ethanol has a higher boiling point than ethane. Thus, **Option C is incorrect.**

### Step 4: Analyze Option D
**Statement:** Ethane is a nonlinear molecule.

- **Ethane Structure:** C2H6

**Molecular Geometry:**
- Ethane has a tetrahedral geometry around each carbon atom, but the overall molecule is not linear; it is a saturated hydrocarbon with a three-dimensional shape.

**Conclusion for D:** Ethane is indeed a nonlinear molecule. Thus, **Option D is correct.**

### Final Conclusion
The statements that are not correct are:
- **Option A:** Phenol is more acidic than acetic acid.
- **Option C:** Ethane has a lower boiling point than ethanol.

### Summary of Incorrect Options:
- **Option A** is incorrect.
- **Option C** is incorrect.