Statement 1 : Hydrogen bomb involves not only fusion but also fission reactions to start the fusion whereas atom bomb involves only fission.
Statement 2 : Though energy liberated per fusion is smaller than energy liberated per fission, yet hydrogen bomb is more powerful than atom bomb.

Options

A. Statement 1 is true, statement 2 is true , statement 2 is a correct explanation for statement 2
B. Statement 1 is true, Statement 2 is true, statement 2 is not a correct explanation for statement 2
C. Statement 1 is true, statement 2 is false
D. Statement 1 is false, statement 2 is true

Explanation

To analyze the statements provided in the question, we will break down each statement and evaluate their correctness based on our understanding of nuclear chemistry.

### Step 1: Analyze Statement 1
**Statement 1**: "Hydrogen bomb involves not only fusion but also fission reactions to start the fusion whereas atom bomb involves only fission."

- **Explanation**:
- A hydrogen bomb (thermonuclear bomb) indeed involves both fission and fusion. The initial fission reaction (using heavy elements like uranium or plutonium) generates the extreme temperatures and pressures necessary to initiate the fusion of hydrogen isotopes (like deuterium and tritium).
- An atomic bomb (fission bomb) relies solely on fission reactions, where heavy nuclei split into lighter nuclei, releasing energy.

- **Conclusion**: Statement 1 is **true** because it accurately describes the processes involved in both types of bombs.

### Step 2: Analyze Statement 2
**Statement 2**: "Though energy liberated per fusion is smaller than energy liberated per fission, yet hydrogen bomb is more powerful than atom bomb."

- **Explanation**:
- It is true that the energy released per fusion reaction is generally less than that released per fission reaction. However, the hydrogen bomb is more powerful because it releases energy from both fission and fusion processes. The total energy output from the fusion reactions in a hydrogen bomb is significantly larger than that from the fission reactions in an atomic bomb.

- **Conclusion**: Statement 2 is **true** because the combined energy from both processes in a hydrogen bomb results in a much higher explosive yield compared to an atomic bomb.

### Final Conclusion
Both statements are true:
- Statement 1 correctly describes the processes involved in hydrogen and atomic bombs.
- Statement 2 correctly explains why a hydrogen bomb is more powerful despite the energy differences per reaction type.