1. Which of the following is a physical change?
A) Burning of paper
B) Rusting of iron
C) Melting of ice
D) Cooking of food
Answer: C
2. A chemical change is best described as a change in which:
A) Shape changes only
B) Size changes only
C) A new substance is formed
D) State changes only
Answer: C
3. Which process is an example of a chemical change?
A) Boiling water
B) Cutting wood
C) Souring of milk
D) Breaking glass
Answer: C
4. Freezing of water into ice is a:
A) Chemical change
B) Physical change
C) Nuclear change
D) Permanent change
Answer: B
5. Which of the following involves formation of ash and gases?
A) Evaporation
B) Dissolving salt
C) Burning coal
D) Melting wax
Answer: C
6. Rusting of iron is a:
A) Physical process
B) Temporary change
C) Chemical change
D) Mechanical change
Answer: C
7. Which is a sign of chemical change?
A) Change in color
B) Change in size
C) Change in shape
D) Change in position
Answer: A
8. Tearing of paper is a:
A) Chemical change
B) Physical change
C) Biological change
D) Nuclear change
Answer: B
9. Formation of curd from milk is a:
A) Physical change
B) Reversible change
C) Chemical change
D) Temporary change
Answer: C
10. Which change is usually reversible?
A) Burning of wood
B) Cooking of rice
C) Melting of butter
D) Rusting of iron
Answer: C
11. In which process is energy usually absorbed or released?
A) Physical change only
B) Chemical change only
C) Both equally
D) Neither
Answer: B
12. Breaking a chalk stick is a:
A) Chemical change
B) Nuclear change
C) Physical change
D) Biological change
Answer: C
13. Which of the following is NOT a chemical change?
A) Digestion of food
B) Respiration
C) Photosynthesis
D) Dissolving sugar in water
Answer: D
14. When milk turns sour, it is due to:
A) Physical reaction
B) Chemical reaction
C) Nuclear reaction
D) Mechanical reaction
Answer: B
15. Which change forms a new substance?
A) Cutting vegetables
B) Freezing juice
C) Burning candle
D) Crushing ice
Answer: C
16. Sublimation of naphthalene balls is a:
A) Chemical change
B) Physical change
C) Permanent change
D) Biological change
Answer: B
17. Which is an example of irreversible change?
A) Melting ice
B) Boiling water
C) Burning paper
D) Freezing water
Answer: C
18. Digestion of food in our body is a:
A) Physical change
B) Chemical change
C) Temporary change
D) Mechanical change
Answer: B
19. Change in state of matter is usually a:
A) Chemical change
B) Nuclear change
C) Physical change
D) Biological change
Answer: C
20. Which process produces heat and light?
A) Freezing
B) Evaporation
C) Burning
D) Condensation
Answer: C
21. Formation of gas bubbles during a reaction shows:
A) Physical change
B) Chemical change
C) Mechanical change
D) Temporary change
Answer: B
22. Which is a physical change?
A) Baking bread
B) Rusting nail
C) Melting chocolate
D) Souring milk
Answer: C
23. Tarnishing of silver is a:
A) Physical change
B) Chemical change
C) Temporary change
D) Reversible change
Answer: B
24. Which change can be reversed easily?
A) Burning coal
B) Cooking egg
C) Freezing water
D) Rusting iron
Answer: C
25. Change in shape without new substance formation is:
A) Chemical change
B) Physical change
C) Nuclear change
D) Biological change
Answer: B
26. Which is evidence of chemical reaction?
A) Change in color
B) Formation of precipitate
C) Release of gas
D) All of these
Answer: D
27. Cutting an apple into pieces is a:
A) Chemical change
B) Physical change
C) Permanent change
D) Nuclear change
Answer: B
28. Which is NOT reversible?
A) Melting wax
B) Freezing water
C) Burning wood
D) Boiling water
Answer: C
29. Cooking food mainly involves:
A) Physical change
B) Chemical change
C) Mechanical change
D) Temporary change
Answer: B
30. Which change does NOT produce a new substance?
A) Rusting iron
B) Burning candle
C) Melting ice
D) Souring milk
Answer: C