- Carbon dioxide is necessary for plants. Why do we then consider it as a pollutant?
- How is smog formed?
- Carbon dioxide gas is necessary for plants to perform photosynthesis. It is also a greenhouse gas. Upto a certain concentration (approximately 350 ppm) in atmosphere, it is both a good raw material for photosynthesis as well as essential for keeping the Earth warm.
But, when concentration of CO2 from its specified level rises, it starts acting like a pollutant and causes air pollution and global warming. Due to which temperature of the Earth will increase and polar ice and glaciers will start melting.
- Smog is formed by combination of suspended dust particles with water vapour.