When one substance changes into one or more new substances, it has exhibited a 1. chemical change. 2. chemical reaction. 3. physical change. 4. chemical property?

Option (1) is the correct answer.

Explanation:

Chemical changes are defined as the changes which tend to show difference in chemical composition of a substance.

For example, toxicity, reactivity, combustion etc are all chemical changes.

In a chemical change, there will always be formation of a new compound.

On the other hand, a change which is unable to bring any difference in chemical composition of a substance is known as a physical change.

For example, a change in shape, size, mass, volume etc are all physical changes.

Thus, we can conclude that when one substance changes into one or more new substances, it has exhibited a chemical change.

the molecules move in straight line until they collide with each other or with the walls of the container. collisions are perfectly elastic; when two molecules collide, they change their directions and kinetic energies, but the total kinetic energy is conserved.

explanation: