Which is most soluble in water

Options

A. Oxalic acid
B. Ethyl chloride
C. Ethyl bromide
D. n-Hexane

Answer

To determine which compound is the most soluble in water among the given options, we can analyze the solubility of each compound based on their chemical structure and functional groups.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds mentioned are oxalic acid, ethyl chloride, ethyl bromide, and normal hexane.

2. **Analyze Oxalic Acid**:
- Oxalic acid (C2H2O4) is a dicarboxylic acid, which means it has two carboxyl (-COOH) groups.
- Carboxylic acids are generally polar and can form hydrogen bonds with water, making them soluble.

3. **Analyze Ethyl Chloride and Ethyl Bromide**:
- Ethyl chloride (C2H5Cl) and ethyl bromide (C2H5Br) are alkyl halides.
- While they can interact with water due to their polar C-X bonds (where X is Cl or Br), they do not form hydrogen bonds as effectively as carboxylic acids do.
- Thus, their solubility in water is lower compared to oxalic acid.

4. **Analyze Normal Hexane**:
- Normal hexane (C6H14) is a straight-chain alkane.
- Alkanes are non-polar and do not interact favorably with water, making them insoluble.

5. **Conclusion**:
- Among the compounds analyzed, oxalic acid is the most soluble in water due to its ability to form hydrogen bonds and its polar nature.

### Final Answer:
**Oxalic acid is the most soluble in water among the given compounds.**