Problem 56 - A Complete Resource Book in Chemistry for JEE Main

Question

The greenhouse effect is caused by (a) \(\mathrm{CO}\) (b) NO (c) \(\mathrm{NO}_{2}\) (d) \(\mathrm{CO}_{2}\)

Step-by-Step Solution

Answer

The greenhouse effect is caused by (d) \(\mathrm{CO}_{2}\).

Step 1: Identify the Main Idea

The exercise asks about the cause of the greenhouse effect. To solve this, we need to identify which chemical among the given options primarily contributes to the greenhouse effect.

Step 2: Understand the Greenhouse Effect

The greenhouse effect is a natural process that warms the Earth's surface. It occurs when certain gases, known as greenhouse gases, trap heat from the sun in the Earth's atmosphere, preventing it from escaping into space.

Step 3: Evaluate Each Option

Let's evaluate each chemical option: (a) \(CO\): Carbon monoxide is not a greenhouse gas.(b) NO: Nitric oxide is not a significant greenhouse gas.(c) \(NO_{2}\): Nitrogen dioxide plays a role in air pollution but is not a major greenhouse gas.(d) \(CO_{2}\): Carbon dioxide is a well-known greenhouse gas that contributes to the greenhouse effect.

Step 4: Conclude Based on Evidence

From the evaluation, \(CO_{2}\) is identified as the greenhouse gas responsible for the greenhouse effect, making option (d) the correct choice.

Key Concepts

Greenhouse Gases

Greenhouse gases are crucial for maintaining the temperature of our planet. Without them, Earth would be too cold to sustain life as we know it. These gases have the ability to trap heat within the Earth's atmosphere.
Some of the primary greenhouse gases include:

• Carbon Dioxide (CO₂): Released by burning fossil fuels and through natural processes.
• Methane (CH₄): Emitted by livestock and other agricultural practices.
• Water Vapor: The most abundant greenhouse gas, but acts as a feedback to the climate.
• Nitrous Oxide (N₂O): A byproduct of agricultural and industrial activities.

When sunlight reaches the Earth, it is either reflected back or absorbed. Greenhouse gases capture some of the outgoing heat, which keeps our planet warm. This natural effect allows life to flourish. However, human activities are increasing the concentration of these gases, leading to more heat being trapped—resulting in global warming.

Carbon Dioxide

Carbon dioxide, commonly known as CO₂, is one of the most significant contributors to the greenhouse effect. It plays a key role in regulating Earth's temperature.
Here are some important points about carbon dioxide:

• Source: It is released by natural processes such as respiration and volcanic eruptions, and by human activities including burning fossil fuels like coal, oil, and gas.
• Role in the Atmosphere: CO₂ absorbs infrared radiation, trapping heat in the atmosphere.
• Impact: The increased CO₂ levels enhance the greenhouse effect, leading to climate change and global warming.

In recent decades, the concentration of CO₂ in the atmosphere has risen dramatically due to human activities. This has raised concerns about its impact on the climate. Efforts to reduce CO₂ emissions, such as transitioning to renewable energy sources, are critical in addressing these challenges.

Environmental Chemistry

Environmental chemistry involves the study of chemical processes that occur in our environment. This includes the impact and behavior of natural and man-made chemicals.
Some essential concepts within environmental chemistry include:

• Pollution: The introduction of contaminants into the environment. This can come from sources like industrial waste and emissions from vehicles.
• Chemical Cycles: Understanding cycles such as the carbon cycle helps explain the movement of different chemicals in nature.
• Environmental Impact Assessment: Analyzing the effects of human activities on the environment to mitigate damage.

Environmental chemistry offers insights into how substances interact with ecosystems and the atmosphere. By studying these interactions, scientists can devise strategies to reduce pollution and manage resources effectively, ensuring a more sustainable future for our planet.