Question

How can we say that a equation is exothermic or endothermic

Answer 1

For equation: If the energy during the reaction is expressed by a negative                       sign then it means that energy is released and reaction will be exothermic.

                      While energy expressed with positive sign is regarded is energy          provided by us and rex is endothermic.

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Answer 2

Answer:

• If the energy level difference between substrate (S) and product (P) is such that P is at a lower level than ‘S’ the reaction is said to be exothermic, whereas when substrate (S) is at lower level than product (P), the reaction is endothermic.