Question

Which of the following is not a pollutant?

• A. SO₂
• B. CO₂
• C. CO
• D. NO₂

Answer 1

The correct option is B

CO₂

The correct option is B.

Explanation of correct option:

1. The harmful substances present In the atmosphere, which hampers the ecological system are air pollutants.
2. These come in distinct forms like gases, particulates, and biological molecules.
3. Carbon dioxide (CO₂) is not a kind of pollutant.
4. It is produced naturally by humans and animals as a byproduct of metabolic activities.
5. It is accountable for sustaining the temperature of the atmosphere.
6. The plants use carbon dioxide as an essential element at the time of photosynthesis.
7. The process in which plants and other organisms use sunlight, water, and carbon dioxide for the production of sugar is known as photosynthesis.
8. Thus, carbon dioxide cannot be considered a pollutant.

Explanation of incorrect options:

Option A:

1. Sulphur dioxide (SO₂) is a part of groups of gaseous air pollutants.
2. The prime source of sulphur dioxide is the burning of coal and oil in power plants.
3. It influences the environment by producing acidic components in the air that falls on the ground in the form of acid rain.

Option C:

1. Carbon monoxide (CO) is colorless, odorless, tasteless, and toxic in nature.
2. The toxicity of the gas makes it an air pollutant.
3. It is generated by the incomplete combustion of hydrocarbons and fuels like coal, oil, and natural gas.
4. The prime source of carbon monoxide emission is vehicles.

Option D:

1. Nitrogen dioxide (NO₂) is also a gaseous air pollutant.
2. It is generated by the combustion of fossil fuels.
3. In the air, its presence results in the formation of other air pollutants like particulate matter and ozone.

Final answer: CO₂ is not a pollutant.