Question

Classify each of the following changes as Physical or Chemical:

Answer 1

Explanation:

Physical changes are the changes that does not lead to any change in chemical composition of a substance.

For example, mass, density, volume are all physical changes.

On the other hand, a change that leads to formation of a new compound by changing the chemical composition of reactants or combining atoms is known as a chemical change.

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

Therefore, given changes are identified as follows.

• Coal burning : It is a combustion reaction. Hence, it is a chemical change.

• Ice melting : Physical state of water changes from solid to liquid. Hence, it is a physical change.

• mixing chocolate syrup with milk : No new compound is forming as there is no chemical reaction occurring. Hence, it is also a physical change.

• explosion of a firecracker : It shows reactivity of fire cracker. Hence, it is a chemical reaction.

• magnetizing of a screwdriver : It shows physical attraction between the magnet and screwdriver. Hence, it is a physical change.