What characterizes a physical change?

A physical change is characterized as a transformation where matter changes from one form to another without altering its chemical composition. This means that the substances present before and after the change remain the same in terms of their chemical properties. For instance, when ice melts into water, it undergoes a physical change as it changes its state from solid to liquid, but the chemical structure of H2O remains unchanged throughout the process.

In contrast, the other options describe changes that involve chemical reactions or significant energy requirements that do not define physical changes. Therefore, recognizing that a physical change can occur without affecting the chemical identity of the substance is essential in understanding the nature of matter and its properties.