Which of the following is most reactive ?

Options

A. `H_(2)`
B. H (nascent)
C. `D_(2)`
D. H (atomic)

Answer

To determine which type of hydrogen is the most reactive among the given options (hydrogen, nascent hydrogen, deuterium, and atomic hydrogen), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Types of Hydrogen**:
- We have four types of hydrogen to consider:
- Molecular hydrogen (H₂)
- Nascent hydrogen (H in its reactive form)
- Atomic hydrogen (H in its atomic form)
- Deuterium (D₂, which is a stable isotope of hydrogen)

2. **Understand Stability and Reactivity**:
- The stability of hydrogen types is as follows:
- Molecular hydrogen (H₂) is the most stable.
- Nascent hydrogen (H) is less stable than molecular hydrogen but more stable than atomic hydrogen.
- Atomic hydrogen (H) is the least stable and very reactive.
- The order of reactivity is the opposite of stability:
- Atomic hydrogen > Nascent hydrogen > Molecular hydrogen.

3. **Analyze Each Option**:
- **Molecular Hydrogen (H₂)**: This is stable and therefore not very reactive.
- **Hydrogen (H)**: This refers to molecular hydrogen in general, which is also stable.
- **Deuterium (D₂)**: This is a stable isotope of hydrogen, hence less reactive.
- **Atomic Hydrogen (H)**: This is highly reactive due to its instability.

4. **Conclusion**:
- Based on the analysis, atomic hydrogen is the most reactive form of hydrogen because it is unstable and readily reacts to form more stable compounds.

### Final Answer:
The most reactive type of hydrogen is **atomic hydrogen**.

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