The inert gas present in atmosphere are

Options

A. He and Ne
B. He, Ne and Ar
C. He, Ne ,Ar and KR
D. He, Ne, Ar, Kr and Xe

Answer

To determine the inert gases present in the atmosphere, we can follow these steps:

### Step 1: Identify the Inert Gases
The inert gases, also known as noble gases, are a group of elements in Group 18 of the periodic table. These gases include:
- Helium (He)
- Neon (Ne)
- Argon (Ar)
- Krypton (Kr)
- Xenon (Xe)
- Radon (Rn)

### Step 2: Analyze Their Presence in the Atmosphere
While all the noble gases are known, not all of them are present in significant amounts in the Earth's atmosphere. We need to check which of these gases are found in the atmosphere and in what proportions.

### Step 3: Exclude Radon
Radon is a radioactive noble gas with a very short half-life, which means it decays quickly and is not found in the atmosphere in significant amounts. Therefore, we can exclude Radon from our list.

### Step 4: List the Remaining Inert Gases
The remaining inert gases that are present in the atmosphere are:
- Helium (He)
- Neon (Ne)
- Argon (Ar)
- Krypton (Kr)
- Xenon (Xe)

### Step 5: Present Proportions
The approximate proportions of these gases in the atmosphere are:
- Helium: 0.00053%
- Neon: 0.0018%
- Argon: 0.95%
- Krypton: 0.0001%
- Xenon: 0.000087%

### Conclusion
Thus, the inert gases present in the atmosphere are Helium, Neon, Argon, Krypton, and Xenon.

### Final Answer
The inert gases present in the atmosphere are: **Helium, Neon, Argon, Krypton, and Xenon.**

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