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.

Living in the atmosphere of CO is dangerous because it : 

1. Combines with O₂ present inside to form CO₂

2. Reduces organic matter of tissues.

3. Combines with haemoglobin and makes it incapable to absorb oxygen.

4. Dilutes the blood.

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 incorrect statement about carbon monoxide is-

A factory was started near a village. Suddenly villagers started feeling the presence of irritating vapors in the village and cases of headache, chest pain, cough, dryness of throat, and breathing problems increased. Villagers blamed the emissions from the chimney of the factory for such problems. This is : 

1. Due to the burning of fossil fuels such as gasoline, coal, natural gas, etc.

2. Due to the burning of toxic soil.

3. Due to the burning of white Phosphorus in soil.

4. Due to Excessive sound pollution.

A gas that is not common component of photochemical smog is-

1. Ozone

2. Acrolein

3. Peroxyacetyl nitrate

4. Chlorofluorocarbons

Consequence(s) of ozone hole is/are:

The gas that damages the ozone layer is -

1. CFCs 

2. CO₂

3. CH₄ 

4. SO₂

Ozone is a very toxic gas and a strong oxidizing agent. It is still useful for life on earth :

1. because it traps harmful UV-rays.

2. because it balances global warming.

3. because it traps harmful X-rays.

4. because it  traps harmful $\mathrm{\gamma }$-rays.