Phenol is more acidic than

Options

A.
B.
C. `C_(2)H_(2)`
D. Both (a) and (c)

Explanation

To determine which compounds are less acidic than phenol, we need to analyze the acidity of phenol and compare it with other compounds.

### Step-by-Step Solution:

1. **Understanding Phenol's Acidity**:
- Phenol (C6H5OH) is a weak acid. When it donates a proton (H+), it forms phenoxide ion (C6H5O-).
- The phenoxide ion is stabilized by resonance, which makes phenol more acidic than many other alcohols.

2. **Comparing with Other Compounds**:
- To find out which compounds are less acidic than phenol, we can compare it with other known acids.
- For example, alcohols (like ethanol) are generally less acidic than phenol because their conjugate bases (alkoxide ions) are not as stabilized by resonance.

3. **Analyzing Given Options**:
- **Option A**: A phenol derivative compound (which could be more or less acidic depending on substituents).
- **Option B**: Paranitrophenol, which is actually more acidic than phenol due to the electron-withdrawing nitro group that stabilizes the phenoxide ion.
- **Option C**: Acetylene (C2H2), which is a weak acid but still less acidic than phenol.

4. **Conclusion**:
- Based on the analysis, phenol is more acidic than acetylene (C2H2) and certain alcohols, but less acidic than paranitrophenol.
- Therefore, the correct answer is that phenol is more acidic than acetylene (C2H2).

### Final Answer:
Phenol is more acidic than acetylene (C2H2).