The most reactive noble gas element is

Options

A. He
B. Ne
C. Kr
D. Xe

Answer

To determine the most reactive noble gas element from the options given (helium, neon, krypton, xenon), we can follow these steps:

### Step-by-Step Solution:

1. **List the Noble Gases**: Write down the noble gases provided in the question.
- Helium (He)
- Neon (Ne)
- Krypton (Kr)
- Xenon (Xe)

2. **Understand Atomic Size and Ionization Energy**: Recognize that as you move down the group of noble gases in the periodic table, the atomic size increases due to an increase in atomic number.

3. **Analyze Ionization Energy Trends**: Understand that with an increase in atomic size, the ionization energy decreases. Ionization energy is the energy required to remove an electron from an atom. A lower ionization energy means it is easier to remove an electron, making the atom more reactive.

4. **Compare the Noble Gases**:
- **Helium**: Smallest size, highest ionization energy, least reactive.
- **Neon**: Larger than helium, but still relatively high ionization energy, less reactive than xenon.
- **Krypton**: Larger than neon, lower ionization energy than neon, more reactive than neon.
- **Xenon**: Largest size, lowest ionization energy, most reactive among the noble gases.

5. **Conclusion**: Based on the analysis, xenon has the lowest ionization energy and is therefore the most reactive noble gas among the options provided.

### Final Answer:
The most reactive noble gas element is **Xenon (Xe)**.

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