The gas that damages the ozone layer is -

1. CFCs 

2. CO₂

3. CH₄ 

4. SO₂

The phenomenon in which atmospheric gases trap the heat radiations from the sun near the earth’s surface and keeps it warm is known as-

1. Natural greenhouse effect

2. Tyndall effect

3. Heating effect

4. Joule’s effect

Domestic waste will lead to : 

1. Biodegradable pollution

2. Nondegradable pollution

3. Thermal pollution of soil

4. Air pollution

... is not a greenhouse gas :-
1. Hydrogen
2. Carbon dioxide
3. Methane
4. Nitrous oxide or $N_{2}O$

Acid rain occurs due to the presence of : 

1. $S{O}_2$ in the atmosphere

2. $N{H}_3$  in the atmosphere

3. $C{O}_2$  in the atmosphere

4. $N_{2}O$  in the atmosphere

Ozone depletion occurs in : 

1. Tropospheric pollution.

2. Stratospheric  pollution.

3. Air pollution.

4. Photochemical smog.

Major component of acid rain is : 

1. ${\mathrm{HNO}}_3$ 

2. ${\mathrm{H}}_2{\mathrm{SO}}_4$

3. HCl

4. ${\mathrm{H}}_2{\mathrm{CO}}_3$

The incorrect statement about carbon monoxide is-

‘White lung cancer’ is caused by : 

1. Asbestos

2. Silica

3. Textiles

4. Paper

Incorrect statement among the following is: 

1. Oxides of sulphur, nitrogen, and carbon are the most widespread air pollutant.

2. pH of drinking water should be between 6.5 and 8.5.

3. Concentration of dissolved oxygen below 6 ppm is good for the growth of fish.

4. Clean water would have a BOD value of less than 5 ppm.