Which of the following components of air is present in the largest amount in the atmosphere?

Options

A. Nitrogen
B. Oxygen
C. Water vapour
D. Carbon dioxide

Answer

To determine which component of air is present in the largest amount in the atmosphere, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Components of Air**:
The main components of air that we need to consider are:
- Nitrogen (N2)
- Oxygen (O2)
- Water vapor (H2O)
- Carbon Dioxide (CO2)

2. **Understand the Composition of Air**:
- Nitrogen is the most abundant gas in the atmosphere.
- Oxygen is the second most abundant gas.
- Water vapor and carbon dioxide are present in much smaller amounts.

3. **Check the Percentages**:
- Nitrogen: Approximately 78%
- Oxygen: Approximately 21%
- Carbon Dioxide: Approximately 0.03%
- Water vapor and other gases combined: Approximately 1%

4. **Compare the Percentages**:
From the percentages, we can see that:
- Nitrogen (78%) is much greater than Oxygen (21%).
- Both Water vapor and Carbon Dioxide are significantly less than Nitrogen and Oxygen.

5. **Conclusion**:
Since nitrogen is present in the largest amount, we conclude that nitrogen is the component of air that is present in the largest amount in the atmosphere.

### Final Answer:
The component of air that is present in the largest amount in the atmosphere is **Nitrogen**.

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