1. burning of any materials
2. rusting of iron
3. cooking of food
4. spoilage of food
5. fermentation
6. denaturation of protein through boiling
7. mixing of acids and bases
8.curdling of milk
9. decaying of organic material
10. chewing of carbohydrate
11. action of enzymes on food
12. tarnishing of silver
13. putrefaction
14. production of salts from heavy metal
15. precipitation
16. burning of gasoline
17. ripening of fruits
18. production of acid rain
19. application of heat on magnesium
20. growth also involves chemical change
