The document discusses reversible and irreversible changes. Reversible changes can go forward or backward and do not result in new substances, such as folding paper or melting butter. Irreversible changes result in one or more new substances and cannot be undone, like burning wood or iron rusting. Examples are provided of both reversible changes like freezing orange juice and irreversible changes like burning a matchstick.

1. Reversible and Irreversible
change

2. Reversible change
A change that can go forward
or backward

3. Reversible change

4. Reversible change

5. Reversible change
Is a change that doesn’t results
in a new substance.

6. Irreversible change
Is a change that results in one or
more new substance.

7. Irreversible change

8. Irreversible change

9. Irreversible change

10. Is it reversible or irreversible change ?
Folded paper
reversible

11. Is it reversible or irreversible change ?
Blowing a balloon
reversible

12. Is it reversible or irreversible change ?
Burning wood
irreversible

13. Is it reversible or irreversible change ?
Iron rust
irreversible

14. Is it reversible or irreversible change ?
Melting butter
reversible

15. Is it reversible or irreversible change ?
Burning match stick
irreversible

16. Is it reversible or irreversible change ?
Toasting bread
irreversible

17. Is it reversible or irreversible change ?
Freezing orange juice
reversible

18. Is it reversible or irreversible change ?
Dissolving salt in water
reversible

19. Is it reversible or irreversible change ?
Melting wax
Burning thread irreversible
reversible

20. Is it reversible or irreversible change ?
Ice turning into water
reversible