In which of the following, the `DeltaH_(h)^(@)` is maximum ?

Options

A. `CH_(2)=CH_(2)`
B. `CH_(2)=C=CH_(2)`
C.
D.

Explanation

To determine which compound has the maximum heat of hydrogenation (ΔH_h^(@)), we need to analyze the stability of the compounds provided. The heat of hydrogenation is inversely related to the stability of the alkene; that is, the less stable the alkene, the higher the heat of hydrogenation.

### Step-by-Step Solution:

1. **Understanding Heat of Hydrogenation**:
- Heat of hydrogenation (ΔH_h^(@)) refers to the enthalpy change when hydrogen is added to an alkene to form an alkane.
- More stable alkenes release less heat upon hydrogenation, while less stable alkenes release more heat.

2. **Analyzing Stability of Compounds**:
- The stability of alkenes can be influenced by factors such as the degree of substitution, conjugation, and steric hindrance.
- Generally, the order of stability for alkenes is as follows:
- Tetrasubstituted > Trisubstituted > Disubstituted > Monosubstituted > Unsubstituted.
- Additionally, conjugated systems are more stable than non-conjugated systems, and cumulative dienes are the least stable.

3. **Identifying the Given Compounds**:
- Let's categorize the compounds based on their types:
- **Normal Alkene**: Typically more stable than cumulative and non-conjugated dienes.
- **Cumulative Diene**: Least stable due to lack of resonance stabilization.
- **Conjugated Diene**: More stable than cumulative but less stable than normal alkenes.
- **Non-Conjugated Diene**: More stable than cumulative but less stable than conjugated.

4. **Comparing Stability**:
- From our analysis:
- Cumulative Diene < Non-Conjugated Diene < Conjugated Diene < Normal Alkene.
- Since the cumulative diene is the least stable, it will have the highest heat of hydrogenation.

5. **Conclusion**:
- Therefore, the compound with the maximum ΔH_h^(@) is the **Cumulative Diene**.

### Final Answer:
The compound with the maximum ΔH_h^(@) is the **Cumulative Diene**.