Assertion (A) : The amount of ozone in the atmosphere began to drop sharply in the 1980s. Reason (R) : The oxygen atoms combine with molecular oxygen to form ozone.

Our Environment

Ozone Layer

Options

(A)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

(B)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).

(C)Assertion (A) is true, but Reason (R) is false.

(D)Assertion (A) is false, but Reason (R) is true.

Official Answer

The amount of ozone in the atmosphere began to drop sharply in the 1980s. However, the reason for this is not that the oxygen atoms combine with molecular oxygen to form ozone. The depletion of the ozone layer is mainly due to the release of synthetic chemicals like chlorofluorocarbons (CFCs) which are used as refrigerants and in fire extinguishers.

Hint

The depletion of the ozone layer is mainly due to the release of synthetic chemicals like chlorofluorocarbons (CFCs) which are used as refrigerants and in fire extinguishers.

Analysis & Explanation

The question requires the student to analyze the given assertion and reason and identify the correct relationship between them.

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Frequently Asked Questions

How many marks does this question carry in CBSE Class 10 Science 2025?

This question carries 1 mark in the CBSE Class 10 Science 2025 examination.

Which chapter does this question come from in Science?

This question is from the chapter "Our Environment" in the CBSE Class 10 Science syllabus.

What topic does this question cover in Science?

This question covers the topic "Ozone Layer" from CBSE Class 10 Science.

What type of question is this in the CBSE Class 10 Science 2025 paper?

This is a MCQ question from Section A in the CBSE Class 10 Science 2025 paper.