Answer: Option (b) is the correct answer.
Explanation:
A change that does not lead to any difference in chemical composition of a substance is known as a physical change.
For example, shape, size, mass, volume, density, boiling point, etc of a substance are all physical properties.
On the other hand, changes that lead to bring change in chemical composition of a substance is known as a chemical change.
For example, exploding dynamite, rotting cheese, combustion, oxidation etc are all chemical changes.
Thus, we can conclude that the statement a physical change is a change from one state of matter to another; a chemical change results in a new substance formed, is correct.
