Percentage of oxygen and carbon dioxide in air is respectively

Options

A. 21% and 0.03%
B. 78% and 0.03 %
C. 78% and 21%
D. 21% and 1%

Answer

To find the percentage of oxygen and carbon dioxide in air, we can follow these steps:

### Step 1: Understand the Composition of Air
Air is a mixture of various gases. The primary components of air include nitrogen, oxygen, carbon dioxide, and trace amounts of other gases.

### Step 2: Identify the Major Components
From the information provided, we know:
- Nitrogen (N2) constitutes approximately 78% of air.
- Oxygen (O2) constitutes approximately 21% of air.
- Carbon Dioxide (CO2) constitutes approximately 0.03% of air.

### Step 3: Write Down the Percentages
Based on the data:
- Percentage of Oxygen in air = 21%
- Percentage of Carbon Dioxide in air = 0.03%

### Step 4: Conclude the Answer
The percentages of oxygen and carbon dioxide in air are respectively:
- Oxygen: 21%
- Carbon Dioxide: 0.03%

### Final Answer
The percentage of oxygen and carbon dioxide in air is respectively 21% and 0.03%.

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