Problem 75 - A Complete Resource Book in Chemistry for JEE Main

Question

Match the list I and list II and pick the correct matching from the codes given below. List (a) Peroxy acetyl nitrate (b) Polycyclic aromatic hydrocarbons (c) Dioxins List II 1\. Waste incineration 2\. Global warming 3\. Photochemical smog 4\. Carcinogens 5\. Vat dye (e) IR active molecules (a) a 3, b 4, c 1, d 5, e 2 (b) a \(2, \mathrm{~b} 3, \mathrm{c} 5, \mathrm{~d} 4, \mathrm{e} 1\) (c) a \(5, \mathrm{~b} 3, \mathrm{c} 1, \mathrm{~d} 2, \mathrm{e} 4\) (d) a \(1, \mathrm{~b} 2, \mathrm{c} 3, \mathrm{~d} 4, \mathrm{e} 5\)

Step-by-Step Solution

Answer

The correct option is (a).

Step 1: Match Peroxy Acetyl Nitrate

Peroxy acetyl nitrate is a component of photochemical smog. Therefore, it matches with 3 from List II.

Step 2: Match Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons are known to be carcinogens. Therefore, they match with 4 from List II.

Step 3: Match Dioxins

Dioxins are by-products of various industrial processes, like waste incineration. Therefore, they match with 1 from List II.

Step 4: Determine the Correct Option

Based on the matches: (a) 3, (b) 4, (c) 1. This matches option (a), which consists of: a 3, b 4, c 1.

Key Concepts

Photochemical Smog

Photochemical smog is a type of air pollution that results from the interaction of sunlight with pollutants such as nitrogen oxides and volatile organic compounds. These pollutants are mainly emitted by vehicles and industrial activities. When these chemicals react in the atmosphere, they create a variety of hazardous compounds, including ozone and peroxy acetyl nitrate (PAN). PAN is particularly harmful as it irritates eyes and impairs respiratory functions. It is one of the key components of photochemical smog, which is prevalent in urban areas with heavy traffic and industrial emissions. This smog tends to be worse in the summer when the sunlight is more intense, leading to higher rates of chemical reactions. The consequences of photochemical smog are vast. It reduces air quality, affects human health, and can also harm ecosystems. Sensitive individuals such as children, the elderly, and those with pre-existing health conditions are particularly at risk from this form of air pollution. Key points about photochemical smog:

• Contains harmful chemicals like ozone and PAN.
• Primarily caused by vehicle emissions and industrial activities.
• Aggravated by sunlight and typically worse in summer months.

Understanding the components and effects of photochemical smog can help in formulating strategies to reduce emissions and improve air quality.

Carcinogens

Carcinogens are substances that can lead to cancer. They interfere with the cellular processes, causing abnormal cell growth that can develop into tumors. One well-known group of carcinogens is polycyclic aromatic hydrocarbons (PAHs), often found in industrial emissions, cigarette smoke, and even charred foods. PAHs result from the incomplete combustion of organic matter. This includes fossil fuels and vegetation. Due to their strong structure, they can be quite pervasive in the environment. Exposure to PAHs can happen through inhalation, ingestion, or skin contact. Once in the body, these compounds can damage the DNA within cells, potentially leading to cancer with prolonged exposure. The identification and regulation of carcinogens like PAHs have made significant strides in protecting the public from associated health risks. Reducing exposure, especially in occupational settings and through public health policies, helps in mitigating their effects. Key points about carcinogens:

• Can cause abnormal cell growth and lead to cancer.
• PAHs are common carcinogens found in smoke and certain charred foods.
• Prolonged exposure increases cancer risk.

Recognizing carcinogens and avoiding them is critical to maintaining health and preventing cancer.

Waste Incineration

Waste incineration is a waste treatment process that involves burning waste materials. It is an effective way to reduce the volume of waste and is widely used for the disposal of non-recyclable materials. However, this process can generate harmful by-products such as dioxins. Dioxins are a group of chemically related compounds that are persistent environmental pollutants (POPs). They are toxic and can cause serious health effects, including reproductive and developmental problems, damage to the immune system, and are considered probable carcinogens. Dioxins can accumulate in the food chain, mainly in the fatty tissues of animals, leading to human exposure through food consumption. The regulation of emissions from waste incineration plants is critical in minimizing dioxin release. Advanced technologies and scrubbers are utilized in modern incineration facilities to capture pollutants before they are released into the atmosphere. Key points about waste incineration:

• Reduces waste volume, but generates toxic by-products like dioxins.
• Dioxins pose significant health and environmental hazards.
• Controlled incineration processes help mitigate negative effects.

Efficient waste management and improved incineration techniques are crucial for minimizing environmental impact and protecting public health.