Most and least abundant inert gases in atmosphere interms of percentage by volume are respectively

Options

A. `Ar, He`
B. `Ar, Xe`
C. `Ar, Kr`
D. `Ar, N e`

Answer

To solve the question regarding the most and least abundant inert gases in the atmosphere in terms of percentage by volume, we can follow these steps:

### Step 1: Identify the Noble Gases
The noble gases, also known as inert gases, include:
- Helium (He)
- Neon (Ne)
- Argon (Ar)
- Krypton (Kr)
- Xenon (Xe)
- Radon (Rn)

### Step 2: Understand Their Abundance in the Atmosphere
We need to know the relative abundance of these gases in the Earth's atmosphere. Generally, the approximate volume percentages of noble gases in the atmosphere are as follows:
- Argon (Ar): ~0.93%
- Neon (Ne): ~0.0018%
- Helium (He): ~0.0005%
- Krypton (Kr): ~0.0001%
- Xenon (Xe): ~0.000009%

### Step 3: Determine the Most Abundant Noble Gas
From the data, we can see that Argon (Ar) has the highest percentage by volume in the atmosphere, making it the most abundant inert gas.

### Step 4: Determine the Least Abundant Noble Gas
Xenon (Xe) has the lowest percentage by volume in the atmosphere, making it the least abundant inert gas.

### Conclusion
Thus, the most abundant inert gas in the atmosphere is Argon (Ar), and the least abundant is Xenon (Xe).

### Final Answer
Most abundant inert gas: Argon (Ar)
Least abundant inert gas: Xenon (Xe)

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