Question

write any three observation is an activity which suggest that a chemical reaction has taken place​

Answer 1

Answer:

change in temperature.

change in colour

Evolution of gas.

Answer 2

Answer:

Also, when calcium carbonate is heated, it decomposes to form calcium oxide and carbon dioxide. In this reaction, calcium carbonate breaks down to form calcium oxide and carbon dioxide. Here, evolution of the gas (carbon dioxide) confirms that a chemical reaction has taken place.

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