Greatest amount of hydration is in

Options

A.
B.
C.
D. all are equal

Answer

To determine where the greatest amount of hydration occurs, we need to analyze the options provided and understand the concept of hydration in organic chemistry.

### Step-by-Step Solution:

1. **Understanding Hydration**:
- Hydration refers to the addition of water (H₂O) to a compound. In organic chemistry, this often involves the nucleophilic attack of the hydroxide ion (OH⁻) on an electrophilic center, typically a carbon atom that is electron-deficient.

2. **Identifying Electrophilic Centers**:
- The carbonyl carbon (C=O) in aldehydes and ketones is a common site for nucleophilic attack due to its electron deficiency. We need to identify which compound has the most electrophilic carbonyl carbon.

3. **Analyzing the Options**:
- Let's consider the options provided:
- **Option 1**: A compound with a ring structure.
- **Option 2**: A compound with a bromine substituent (Br) that exerts a -I (inductive) effect, decreasing electron density.
- **Option 3**: A compound with a bromine substituent and a carbonyl group, likely an aldehyde.

4. **Evaluating the Effects of Substituents**:
- The -I effect of bromine pulls electron density away from the carbonyl carbon, making it more electrophilic.
- In the case of aldehydes (like in Option 3), the carbonyl carbon is more electrophilic than in ketones due to the presence of hydrogen atoms, which do not exert a strong electron-withdrawing effect compared to alkyl groups.

5. **Comparing Electrophilicity**:
- Between the options, the compound in Option 3, which is an aldehyde, will have a more pronounced electrophilic character due to the influence of the bromine atom and the nature of the aldehyde functional group.

6. **Conclusion**:
- The greatest amount of hydration will occur in the compound represented by **Option 3**, as it has the most favorable conditions for nucleophilic attack by the hydroxide ion.

### Final Answer:
The greatest amount of hydration is in **Option 3**.

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