The gaseous envelope around the earth is known as atmosphere. The region lying between an altitudes of 11 - 50 km is __________.

Photo chemical smog formed in congested metropolitan cities mainly consists of ___________

Ozone depletion will cause ___________.

Release of oxides of nitrogen and hydrocarbons into the atmosphere by motor vehicles is prevented by using __________.

Biochemical oxygen Demand value less than 5 ppm indicates a water sample to be ___________.

Which is considered to be earth’s protective umbrella ? Why ?

What are degradable and nondegradable pollutants ?

Explain how does greenhouse effect cause global warming.

Dissolved oxygen in water is responsible for aquatic life. What processes are responsible for the reduction in dissolved oxygen in water ?

Explain how oxygen deficiency is caused by carbon monoxide in our blood ? Give its effect

What are the various methods you suggest to protect our environment from pollution ?

Ethane burns completely in air to give CO₂, while in a limited supply of air gives CO. The same gases are found in automobile exhaust. Both CO and CO₂ are atmospheric pollutants
i) What is the danger associated with these gases
ii) How do the pollutants affect the human body ?

Differentiate the following
(i) BOD and COD
(ii) Viable and non-viable particulate pollutants