Environmental chemistry is best defined as : 

1. Study of chemical processes in nature.

2. Study of biochemical processes in nature.

3. Both (1) and (2) 

4. None of the above.

Tropospheric pollution arises due to the presence of:

CO gas is more dangerous than CO₂ gas because : 

1. CO is capable of forming a complex with haemoglobin (carboxyhemoglobin), that is more stable than the oxygen-haemoglobin complex. 

2. CO is capable of forming a complex with haemoglobin (carboxyhemoglobin), that is less stable than the oxygen-haemoglobin complex. 

3. CO₂ is capable of forming a complex with haemoglobin (carboxyhemoglobin), that is more stable than the oxygen-haemoglobin complex. 

4. CO₂ is capable of forming a complex with haemoglobin (carboxyhemoglobin), that is less stable than the oxygen-haemoglobin complex. 

Gases responsible for greenhouse effect are : 
1. Carbon dioxide (CO₂)
2. Ozone (O₃)
3. Nitrous oxide (N₂O)
4. All of the above.

Statues and monuments in India are affected by acid rain because of the formation of : 

The correct statement(s) regarding photochemical smog is/are:

The reaction/s involved during the formation of photochemical smog are:

\(1. \space NO_2(g) \rightarrow NO(g) + \stackrel{\cdot}{O(g)}\)

\(2. \stackrel{\cdot}{O(g)} + O_2(g) \rightarrow O_3(g)\)

\(3.\space O_3(g) + NO(g) \rightarrow NO_2(g) + O_2(g)\)

4. All of the above

The reaction(s) involved in ozone layer depletion in the stratosphere is/are:

1.
2.
3.
4.	All of the above

Consequence(s) of ozone hole is/are:

The major pollutant(s) of water pollution is/are:

1. Pathogens.

2. Organic waste.

3. Chemical components.

4. All of the above.