Final answer:
A chemical reaction can either release or absorb energy. Exothermic reactions release energy, while endothermic reactions absorb energy. option d is correct.
Step-by-step explanation:
A chemical reaction can either release or absorb energy. When the energy released from forming new bonds is greater than the energy needed to break the existing bonds, the reaction releases energy and is called an exothermic reaction.
Examples of exothermic reactions include the combustion of methane gas. On the other hand, when the energy needed to break the existing bonds is greater than the energy released from forming new bonds, the reaction absorbs energy and is called an endothermic reaction. An example of an endothermic reaction is photosynthesis.
In a chemical reaction, energy is either released or absorbed. This is described by the principle of conservation of energy, which states that energy cannot be created or destroyed, only transferred or converted from one form to another. In exothermic reactions, energy is released to the surroundings, while in endothermic reactions, energy is absorbed from the surroundings.
Therefore, the correct statement is that energy changes occur in chemical reactions and can take the form of either release or absorption.