Question

Differentiate between the following changes with suitable examples.

b. Reversible and irreversible changes

Answer 1

Reversible change	Irreversible changes
1. Changes that can be quickly reversed to return to the 'original substance' are known as reversible changes.	1. Irreversible change occur when materials cannot be returned to their original state.
2. It is a temporary change.	2. It is a permanent change.
3. The chemical properties of the substance do not change.	3. The chemical properties of the substance change.
4. Most physical changes are reversible changes.	4. All chemical changes are irreversible changes.
5. Example- ice melts into water and water freezes to form ice.	5. Example- Burning of paper changes into ash and smoke, the paper cannot be obtained back from ash and smoke. Cement mixed with water, the cement cannot be brought back to its original form.