Which of the following elements is present in trace among in the atmospheric air?

Options

A. Argon
B. Nitrogen
C. Oxygen
D. Ozone

Explanation

To determine which element is present in trace amounts in atmospheric air, we can analyze the composition of the air and identify the elements mentioned in the question. Here’s a step-by-step solution:

### Step-by-Step Solution:

1. **Understand the Composition of Atmospheric Air**:
- Atmospheric air is primarily composed of several gases, with the major components being nitrogen, oxygen, argon, and trace gases.

2. **Identify Major Components**:
- Nitrogen (N2) makes up about 78% of the atmosphere.
- Oxygen (O2) constitutes about 21% of the atmosphere.
- Argon (Ar) is present in less than 1% of the atmosphere.

3. **Define Trace Elements**:
- Trace elements are those that are present in very small amounts, typically less than 1% of the total composition.

4. **Analyze the Given Options**:
- If we consider the elements typically found in air, we have:
- Ozone (O3) - not a trace element, as it is a minor component but not a primary one.
- Oxygen (O2) - 21%, not a trace element.
- Nitrogen (N2) - 78%, not a trace element.
- Argon (Ar) - less than 1%, qualifies as a trace element.

5. **Conclusion**:
- Among the options, the element that is present in trace amounts in atmospheric air is **Argon**.

### Final Answer:
- The element present in trace amounts in atmospheric air is **Argon**.

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