Question

Which statement best describes the difference between endothermic and exothermic reactions? They are opposites because endothermic reactions require energy and exothermic reactions release energy. They are opposites because endothermic reactions release energy and exothermic reactions require energy. They the same because they are both ways of forming precipitates. They the same because they are both ways of forming gasses.

Answer 1

Answer: They are opposites because endothermic reactions require energy and exothermic reactions release energy.


Explanation:


An endothermic reaction is that where there is a net consumption of heat energy due to the bonds of the products are more energetical than the bonds of the reactants. This is, it is necessary a higher amount of energy to brake the bonds of the reactants compared with that released when the new bonds of the products are formed.


On the contrary, an exothermic reaction releases more energy than that required to to brake the bonds of the reactants, so the net effect is the release of heat energy.

The endothermic reactions cool down the surroundings while the exothermic reactions heat up the surroundings.

Whenever you have doubts, I recommend you search for an energy diagram which shows the potential energy of the reactants and the products indicating when the net energy is released or consumed.

Answer 2

Endothermic reactions are which absorbs energy from outside the system while exothermic reactions give off or releases energy outside the system. 

Answer:
They are opposites because endothermic reactions require energy and exothermic reactions release energy.