Which of the following chemicals are known to deplete the ozone layer in the atmosphere?

Correct option is C

​The correct answer is (c) CFCs.

Correct Answer Explanation:

• CFCs (Chlorofluorocarbons) are chemicals known to deplete the ozone layer in the Earth's atmosphere.
• CFCs were commonly used in air conditioning, refrigeration, aerosol propellants, and foam-blowing agents.
• When these chemicals are released into the atmosphere, they rise and reach the stratosphere, where they are broken down by ultraviolet (UV) radiation.
• This process releases chlorine atoms, which react with ozone (O₃) molecules, breaking them apart and causing a thinning of the ozone layer.
• The depletion of the ozone layer is a major environmental concern as it allows more harmful UV radiation to reach the Earth's surface, leading to skin cancer, cataracts, and other health issues, as well as damaging ecosystems.

Information about Other Options:

• SO₂ (Sulfur Dioxide) – Incorrect. While sulfur dioxide can cause acid rain, it does not have a significant impact on ozone depletion.
• NO₂ (Nitrogen Dioxide) – Incorrect. Nitrogen dioxide plays a role in the formation of smog and air pollution, but it is not the primary agent for ozone layer depletion.
• CO (Carbon Monoxide) – Incorrect. Carbon monoxide is a harmful gas related to air pollution, but it does not contribute to the depletion of the ozone layer.

Information Booster:

• Ozone Layer Depletion: Knowledge about the chemicals that deplete the ozone layer is crucial for understanding environmental issues.
• CFCs and halons were major culprits in this process, but their production has been banned or reduced due to international agreements like the Montreal Protocol.

Montreal Protocol:

• Adopted: The protocol was adopted on September 16, 1987 in Montreal, Canada, and came into force on January 1, 1989.
• Purpose: The main goal of the Montreal Protocol is to protect the ozone layer, which shields the Earth from harmful ultraviolet (UV) radiation. This radiation is linked to skin cancer, cataracts, and other health problems, as well as to environmental damage such as crop loss and disruption of marine ecosystems.