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Assertion : The main reasons of ozone la...

Assertion : The main reasons of ozone layer delpletion is believed to be the release of chlorofluorocarbon compounds known as freons.
Reason : CFCs are transporting agents for continously generating chlorine radicals into the stratosphere.

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true but reason is not the c orrect explanation of assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To analyze the assertion and reason provided in the question, we will break down the information step-by-step. ### Step 1: Understanding the Assertion The assertion states that the main reason for ozone layer depletion is the release of chlorofluorocarbon (CFC) compounds, commonly known as freons. - **Explanation**: CFCs are synthetic compounds that were widely used in refrigeration, air conditioning, and aerosol propellants. When released into the atmosphere, they eventually reach the stratosphere, where they contribute to the depletion of the ozone layer. ### Step 2: Understanding the Reason The reason given is that CFCs act as transporting agents that continuously generate chlorine radicals in the stratosphere. - **Explanation**: When CFCs reach the stratosphere, they are broken down by ultraviolet (UV) radiation, releasing chlorine atoms. These chlorine atoms can react with ozone (O₃) molecules, leading to the formation of chlorine monoxide (ClO) and oxygen (O₂). This process continues, as the chlorine radicals can regenerate and deplete more ozone. ### Step 3: The Reaction Mechanism 1. **CFCs Release Chlorine**: CFCs are broken down by UV light, releasing chlorine radicals. 2. **Chlorine Radicals React with Ozone**: The chlorine radicals react with ozone, forming ClO and O₂. 3. **Regeneration of Chlorine Radicals**: The ClO can further react with other radicals, leading to the release of more chlorine radicals, which can continue to deplete ozone. ### Step 4: Conclusion Both the assertion and the reason are true, and the reason correctly explains the assertion. The depletion of the ozone layer is indeed primarily due to the release of CFCs, which generate chlorine radicals that react with and deplete ozone. ### Final Answer - **Assertion**: True - **Reason**: True - **Conclusion**: The reason correctly explains the assertion.
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