Question

In which of these do the molecules of substances undergo changes–physical change or chemical change?

Answer 1

In chemical change molecules of substances undergo changes, as in a chemical change molecules reacts with other molecules. Sometimes they combine with other molecules and sometimes they degenerate into smaller molecules. While in a physical change, only the shape size, and color of the substance changes, which does not affect the molecular structure of the substance. Hence, we can say in a chemical change, molecules of the substance undergo changes.