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Chemical Changes and Reaction — CHEMISTRY STD 9 — Question

ICSE BoardEnglish MediumSTD 9CHEMISTRYChemical Changes and Reaction2 Marks
Question
What do you understand by the term? Give example:
Exothermic chemical change.
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Answer

An exothermic reaction is a chemical reaction in which less energy is needed to break bonds in the reactants than is released when new bonds form in the products. During an exothermic reaction, energy is constantly given off, often in the form of heat. All combustion reactions are exothermic reactions

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