Noble gases are also known as aerogens because

Options

A. They occur in air
B. They are rarely found in atmosphere
C. They are most rarely found in atmosphere
D. none of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Noble Gases**: Noble gases are the elements found in Group 18 of the periodic table. These elements include Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and Radon (Rn).

2. **Presence in the Atmosphere**: Most noble gases, except for Radon, are present in the Earth's atmosphere. Radon is radioactive and is not commonly found in the atmosphere.

3. **Abundance of Noble Gases**: The total abundance of noble gases in the atmosphere is approximately 1% by volume. Among these, Argon is the most abundant noble gas.

4. **Reason for the Name 'Aerogens'**: The term 'aerogens' refers to their occurrence in the air. Since noble gases are found in the atmosphere, they are referred to as aerogens.

5. **Conclusion**: Based on the information, the correct reason why noble gases are known as aerogens is that they occur in air.

**Final Answer**: Noble gases are also known as aerogens because they occur in air.

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