Question

state the difference between physical and chemical changes.

Answer 1

In physical changes the original substance can be brought back because there is no change in the chemical property of the substance

in chemical change, there is change in the chemical properties of the substance

Answer 2

Difference between physical and chemical changes :-

# PHYSICAL CHANGES

- The chemical composition of a substance does not change.

- Change is only in the state of matter and not in the chemical identity.

-Examples include- Vaporising of water and dissolution of sugar in water.

- Most changes are reversible.

- No new substances are formed. For example,
Ice → Water → Steam


# CHEMICAL CHANGES

- The chemical composition of a substance changes.

- Change is in chemical identity, but may or may not be in the state of matter.

- Examples include- Rusting of Iron, cooking of food etc.

- Most changes are irreversible.

- New substances are formed.For example,
methane → carbon dioxide and water (on heating)