The incorrect statement about carbon monoxide is-

1.	It reduces the oxygen-carrying ability of blood.
2.	The carboxyhaemoglobin (haemoglobin bound to CO) is less stable than oxyhaemoglobin.
3.	It is produced due to incomplete combustion.
4.	It forms carboxyhaemoglobin.

‘White lung cancer’ is caused by : 

1. Asbestos

2. Silica

3. Textiles

4. Paper

A gas that has the greatest affinity for hemoglobin is :

1. CH₄

2. NO

3. O₂

4. CO₂

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.

The aromatic compound that is present as particulate among the following is : 

1. Benzene

2. Toulene

3. Nitrobenzene

4. Polycyclic hydrocarbons

A non-greenhouse gas is : 
1. CO₂
2. CH₄
3. Chlorofluorocarbons
4. O₂

The most abundant hydrocarbon pollutant is : 
1. Methane
2. Ethane
3. Propane
4. Butane

When rain is accompanied by a thunderstorm, the pH value of the collected rain water is :

1. Dependent upon the amount of dust in the air.

2. Slightly lower when rainwater is without a thunderstorm.

3. Slightly higher when the thunderstorm is not there.

4. Unaffected by the occurrence of thunderstorms.

Gas that is not a pollutant is : 

1. Carbon monoxide

2. Nitrogen peroxide

3. Carbon dioxide

4. Sulphur dioxide

Air pollution from the leakage of methyl isocyanate gas from the union carbide factory in Bhopal caused a major tragedy on:

1. Dec. 2, 1984

2. Dec 15, 1983

3. Dec.10, 1982

4. Dec. 4, 1988