Identifying the Cause of Ozone Layer Depletion
The ozone layer protects Earth from harmful ultraviolet (UV) radiation. Its depletion is a major environmental concern.
Primary Cause of Ozone Depletion
The principal factor causing the depletion of the ozone layer is the emission of Chlorofluorocarbons (CFCs).
- CFCs are synthetic chemicals historically used in refrigerants, aerosol propellants, and solvents.
- When released into the atmosphere, CFCs rise to the stratosphere.
- Here, intense UV radiation causes them to decompose, releasing highly reactive chlorine atoms.
- These chlorine atoms act as catalysts in a destructive cycle, breaking down ozone molecules ($\text{O}_3$) much faster than they are naturally created. The simplified cycle involves:
- $\text{Cl} + \text{O}_3 \rightarrow \text{ClO} + \text{O}_2$
- $\text{ClO} + \text{O} \rightarrow \text{Cl} + \text{O}_2$
Evaluating Other Options
- Aviation fuels: Emissions from high-flying aircraft can release nitrogen oxides, which have a minor impact on ozone, but are not the primary cause.
- Volcanic eruptions: While volcanoes release various gases and particles, their direct impact on the large-scale depletion of the ozone layer is limited compared to CFCs.
- Radioactive rays: These are forms of high-energy radiation. They do not directly participate in the chemical reactions that deplete the ozone layer in the stratosphere.
Therefore, Chlorofluorocarbons are identified as the main culprits responsible for the depletion of the ozone layer.
Similar Questions
- Which of the following in polluted air causes Hay fever?
- Since 2011 the supreme court banned the manufacture, sale and use of which pesticide that causes hazardous effects to human life as well as the environment?
- Which of the following gas is not related to acid rain?
- Which of the following chemicals/gases is/are responsible for causing the greenhouse effect?
- Which of the following is NOT a greenhouse gas?
- Which of the following is the most polluted city of the world as per the Guinness World Records 2020 analysis of a World Health Organization report?
- Ozone layer is responsible for preventing harmful UV rays to enter the earth's atmosphere. Which of the hydrocarbons is/are not responsible for depletion of the ozone layer?
- Read the given statements, labelled Assertion (A) and Reason (R), and select the most appropriate option with respect to them.
Statements:
'A': Carbon dioxide is not always a pollutant.
'R': Plants require carbon monoxide for growth that they get from carbon dioxide. - Acid rain is mainly caused due to the presence of which two gases in the atmosphere?
- Which of the following production activities is the largest emitter of $CO_{2}$?
Important Questions from Environmental pollution
Photochemical smog is a resultant of the reaction among
Which of the following is NOT responsible for the degradation of our environment?
With reference to furnace oil, consider the following statements:
1. It is a product of oil refineries.
2. Some industries use it to generate power.
3. Its use causes sulphur emissions into environment.
Which of the statements given above are correct?
Why is there a concern about copper smelting plants?
1. They may release lethal quantities of carbon monoxide into environment.
2. The copper slag can cause the leaching of some heavy metals into the environment.
3. They may release sulphur dioxide as a pollutant.
Select the correct answer using the code given below.
Magnetite particles, suspected to cause neurodegenerative problems are generated as environmental pollutants from which of the following?
1. Brakes of motor vehicles
2. Engines of motor vehicles
3. Microwave ‘Stoves within homes
4. Power plants
5. Telephone lines
Select the correct answer using the code given below.
