CBSE 2025 · Region 1 · Set 1 · Q21 · 2 marks
A student performs the following experiment in his school laboratory.
List two observations to justify that in this experiment a chemical change has taken place.
List two observations to justify that in this experiment a chemical change has taken place.Marking-scheme solution
Evolution of gas
Change / Rise in temperature
Chemical Reactions and EquationsWriting and Balancing Chemical EquationsUnderstandvery_short_answereasy
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CBSE Class 10 Science past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.