Bhopal gas tragedy of 1984 took place because methyl isocyanate reacted with
1. DDT
2. Ammonia
3. ${\mathrm{CO}}_2$
4. Water

The intensity of noise beyond which physical discomfort is:
1. 70 dB
2. 80 dB
3. 100 dB
4. 120 dB

In coal fired power plants, electrostatic precipitators are fitted to control emission of:
1. ${\mathrm{NO}}_{\mathrm{x}}$
2. CO
3. SPM
4. ${\mathrm{SO}}_2$

Photochemical smog does not contain
1. PAN
2. Ozone
3. Nitrogen dioxide
4. ${\mathrm{CO}}_2$

Which of the following is a secondary pollutant?
1. CO
2. ${\mathrm{O}}_3$
3. ${\mathrm{SO}}_2$
4. ${\mathrm{CO}}_2$

Photochemical smog is formed in traffic congested cities where the conditions are:

1. cool and intense solar radiation            

2. cool and less solar radiation

3. warm and intense solar radiation         

4. warm and less solar radiation

Nitrogen oxides formed during emission from automobiles and power plants are a source of fine airparticles which lead to
1. Dry acid deposition
2. Photochemical smog
3. Wet acid deposition
4. Industrial smog

Which one of the following statements in not valid for aerosols
1. They are harmful to human health
2. They alter rainfall and monsoon patterns
3. They cause increased agricultural productivity
4. They have negative impact on agricultural land

The Air Prevention and Control of Pollution Act came into force in:
1. 1981
2. 1985
3. 1990
4. 1975

dB is a standard abbreviation used for the quantitative expression of
1. A particular pollutant
2. The dominant Bacillus in a culture
3. Certain pesticides
4. The density of bacteria in a medium