Answer the question on the basis of the passage given below:

Molecular nitrogen is very little reactive chemically. During lightning discharge, atmospheric nitrogen and oxygen combine to form nitric acid which also combines with oxygen to form nitrogen dioxide. Both \(NO\) and \(NO_2\) constitute smog which is very poisonous. It can cause a burning sensation in the eyes and adversely affect the respiratory system.

What is the value associated with the control of photochemical smog?

Control of photochemical smog can provide relief from diseases linked with the respiratory system such as cough, cold, bronchitis asthma.

The correct answer is option 1. Control of photochemical smog can provide relief from diseases linked with the respiratory system such as cough, cold, bronchitis asthma.

Photochemical smog is a type of air pollution that results from the interaction of primary pollutants, such as nitrogen oxides (NOx) and volatile organic compounds (VOCs), in the presence of sunlight. The complex chemical reactions that take place lead to the formation of secondary pollutants, including ground-level ozone \((O_3)\) and particulate matter. The constituents of photochemical smog can have various adverse health effects, particularly on the respiratory system. Here's a detailed explanation:

1. Ozone \((O_3)\): Ozone is a major component of photochemical smog and is formed through photochemical reactions involving nitrogen oxides and volatile organic compounds. Ground-level ozone is a respiratory irritant that can cause inflammation of the respiratory tract. Prolonged exposure to ozone can lead to respiratory symptoms such as coughing, throat irritation, and difficulty breathing.

2. Particulate Matter (PM):  Photochemical smog can also contain particulate matter, which includes tiny particles suspended in the air. These particles can penetrate deep into the respiratory system, causing irritation and inflammation. Long-term exposure to particulate matter is associated with respiratory diseases such as bronchitis and can worsen existing respiratory conditions.

3. Nitrogen Dioxide \((NO_2)\):  Nitrogen dioxide is a primary pollutant that contributes to the formation of photochemical smog. It can irritate the lungs and increase the susceptibility to respiratory infections. Individuals with pre-existing respiratory conditions, such as asthma, may experience exacerbation of symptoms when exposed to elevated levels of nitrogen dioxide.

4. Volatile Organic Compounds (VOCs):  VOCs, including formaldehyde and acrolein, are components of photochemical smog that can irritate the respiratory system. These compounds may contribute to the development of respiratory symptoms and can be particularly problematic for individuals with respiratory conditions.

5. Health Effects: Exposure to photochemical smog is linked to a range of respiratory problems, including cough, cold, bronchitis, and aggravation of asthma symptoms. Additionally, vulnerable populations such as children, the elderly, and individuals with pre-existing respiratory conditions are more susceptible to the adverse effects of photochemical smog.

6. Control Measures: To mitigate the health impacts of photochemical smog, control measures focus on reducing the emissions of nitrogen oxides and volatile organic compounds. This includes implementing stricter regulations on vehicle emissions, industrial processes, and other sources of air pollution.

In summary, the control of photochemical smog is crucial for protecting respiratory health. By reducing the emissions of pollutants that contribute to smog formation, we can decrease the incidence of respiratory diseases and improve overall air quality. Public awareness, regulatory measures, and sustainable practices are essential components of effective smog control strategies.