Which of the following statement is correct for the stablity of ions of ethyl alcohol and phenol:

Options

A. Delocalisation of `pi`-electrons in phenoxide ion
B. Delocalisation of electrons in ethoxide ion
C. Inductive effect of ethyl and phenyl group
D. Localisation of `pi`-electrons in phenoxide ion

Answer

To determine which statement is correct regarding the stability of ions of ethyl alcohol and phenol, we need to analyze the structures and stability of the ethoxide ion (from ethyl alcohol) and the phenoxide ion (from phenol).

### Step-by-step Solution:

1. **Identify the Ions**:
- Ethyl alcohol (ethanol) ion: Ethoxide ion (C2H5O⁻) can be represented as CH3-CH2-O⁻.
- Phenol ion: Phenoxide ion (C6H5O⁻) can be represented as C6H5-O⁻.

2. **Analyze the Stability Factors**:
- **Ethoxide Ion**: The ethoxide ion has an oxygen atom with a negative charge. The stability of this ion is influenced by the inductive effect of the ethyl group (C2H5). The ethyl group is an electron-donating group, which increases the electron density on the negatively charged oxygen, making the ion less stable.
- **Phenoxide Ion**: The phenoxide ion has a similar negatively charged oxygen atom. However, the negative charge can be delocalized over the aromatic ring through resonance. This delocalization stabilizes the phenoxide ion significantly.

3. **Evaluate the Options**:
- **Option A**: Delocalization of pi electrons in the phenoxide ion. This is correct because the negative charge on the oxygen can be delocalized into the aromatic ring, stabilizing the ion.
- **Option B**: Delocalization of electrons in the ethoxide ion. This is incorrect because there is no significant delocalization occurring in the ethoxide ion.
- **Option C**: Inductive effect of ethyl and phenyl groups. This is misleading since the inductive effect in the ethoxide ion destabilizes it, while in phenoxide, resonance is the major stabilizing factor.
- **Option D**: Localization of pi electrons in the phenoxide ion. This is incorrect because the pi electrons are delocalized, not localized.

4. **Conclusion**:
- The correct statement regarding the stability of the ions of ethyl alcohol and phenol is **Option A: Delocalization of pi electrons in phenoxide ion**.