Question

How is energy involved in chemical and physical changes?

Answer 1

Energy is involved in both chemical and physical changes. Chemical reactions involve a change in the bonds of the reactants and can either absorb or release energy. Phase changes also involve energy changes.

Step-by-step explanation:

All chemical reactions involve energy. Energy is a property of matter that is defined as the ability to do work. Chemical reactions can either absorb or release energy. Phase changes, such as solid to liquid or liquid to gas, involve changes in energy. For example, when solid dry ice vaporizes, energy is absorbed. When liquid water becomes ice, energy is released. During chemical reactions, the bonds in the reactants are broken and new bonds in the products are formed, resulting in a change in the amount of potential energy in the reaction.

Answer 2

Chemical changes within matter always use energy; physical changes sometimes use energy, though they use much less energy than chemical changes. Physical changes use energy to change the physical state of a substance. Chemical changes either release or absorb energy when changing a substance into a completely new one.