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Science · 2024 · 1 mark
CBSE 2024 · Region 4 · Set 1 · Q20
Assertion (A) : Oxygen is essential for all aerobic forms of life.
Reason (R): Free oxygen atoms combine with molecular oxygen to form ozone.
Official answer
From CBSE’s own marking scheme for this paper.
(B)
Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
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CBSE Class 10 Science past-paper question from the 2024board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.