Question

How do we know if a reaction is endothermic or exothermic?

Answer 1

If in any reaction heat is produced then it is exothermic else it if heat is required to bring fhe reaction. Then endothermic

Answer 2

an exothermic reaction release heat so if the enthalpies of the reactant is greater than the products the reactant will be exothermic. If the products side has a large enthalpy, the reaction is enodothermic reactant

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