Which of the following indicates that an exothermic reaction has taken place?

A. a change in color

B. release of heat and/or light energy

C. cooling of the surroundings

D. absorption of heat by the reaction ...?

Respuesta :

Answer:

The option B is correct option. Which is release of heat and/or light energy .

Explanation:

According to the definition of exothermic reaction :

An exothermic reaction is a chemical reaction that releases energy by light or heat.

From definition option B (release of heat and/or light energy) indicates that an exothermic reaction has taken place.



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Answer: Option (B) is the correct answer.

Explanation:

An exothermic reaction is defined as the chemical reaction in which there occurs release of heat.

For example, [tex]A + B \rightarrow AB + Heat[/tex]

In an exothermic reaction, energy of reactants is more than the energy of products.

Whereas an endothermic reaction is defined as a chemical reaction in which heat is absorbed by reactant molecules.

For example, [tex]A + B + Heat \rightarrow AB[/tex]

In endothermic reaction, energy of reactant molecules is less than the energy of products.

Thus, we can conclude that release of heat and/or light energy indicates that an exothermic reaction has taken place.