NCERT Class 7 Science MCQ | Chapter 5: Changes Around Us: Physical and Chemical
1. Which of the following is a physical change?
(A) Melting of ice
(B) Burning of paper
(C) Rusting of iron
(D) Curdling of milk
Answer: (A) Melting of ice
2. Which of the following is a chemical change?
(A) Cutting paper
(B) Melting wax
(C) Burning wood
(D) Dissolving sugar in water
Answer: (C) Burning wood
3. What is a physical change?
(A) A change in which a new substance is not formed
(B) A change in which a new substance is always formed
(C) A change that can occur only by heating
(D) A change that occurs only in living organisms
Answer: (A) A change in which a new substance is not formed
4. What is a chemical change?
(A) A change in which one or more new substances are formed
(B) A change in which only the shape changes
(C) A change in which only the size changes
(D) A change that can always be reversed
Answer: (A) A change in which one or more new substances are formed
5. Which of the following is an example of a reversible change?
(A) Melting of ice
(B) Burning of paper
(C) Rusting of iron
(D) Cooking food
Answer: (A) Melting of ice
6. Which of the following is generally an irreversible change?
(A) Folding a paper
(B) Melting ice
(C) Burning paper
(D) Freezing water
Answer: (C) Burning paper
7. What happens when ice is heated?
(A) It changes into water
(B) It changes into a new substance
(C) It becomes permanently damaged
(D) It changes directly into soil
Answer: (A) It changes into water
8. Which type of change occurs when water freezes into ice?
(A) Physical change
(B) Chemical change
(C) Biological change
(D) Nuclear change
Answer: (A) Physical change
9. Which of the following is a change in which the shape of a substance changes but its composition remains the same?
(A) Physical change
(B) Chemical change
(C) Combustion
(D) Rusting
Answer: (A) Physical change
10. Which of the following is evidence that a chemical change may have occurred?
(A) Formation of a new substance
(B) Change in shape only
(C) Change in size only
(D) Change in position only
Answer: (A) Formation of a new substance
11. Which of the following is an example of rusting?
(A) Formation of a reddish-brown coating on iron
(B) Melting of iron
(C) Cutting an iron rod
(D) Bending an iron wire
Answer: (A) Formation of a reddish-brown coating on iron
12. What is required for rusting of iron to occur?
(A) Oxygen and moisture
(B) Only sunlight
(C) Only carbon dioxide
(D) Only heat
Answer: (A) Oxygen and moisture
13. Which of the following can help prevent rusting of iron?
(A) Painting the iron surface
(B) Keeping iron in moist air
(C) Scratching the surface
(D) Washing it continuously with water
Answer: (A) Painting the iron surface
14. Which of the following is a chemical change that commonly occurs during cooking?
(A) Formation of new substances in food
(B) Cutting vegetables into pieces
(C) Changing the shape of a plate
(D) Melting ice
Answer: (A) Formation of new substances in food
15. Which of the following is a physical change?
(A) Breaking a glass object into pieces
(B) Burning a wooden stick
(C) Rusting of iron
(D) Digestion of food
Answer: (A) Breaking a glass object into pieces
16. Which statement about physical changes is correct?
(A) No new substance is usually formed
(B) A completely new substance is always formed
(C) They can never be reversed
(D) They occur only at high temperatures
Answer: (A) No new substance is usually formed
17. Which statement about chemical changes is correct?
(A) One or more new substances are formed
(B) Only the shape of a substance changes
(C) The original substance always remains unchanged
(D) They are always reversible
Answer: (A) One or more new substances are formed
18. What happens when a piece of paper is torn into smaller pieces?
(A) It undergoes a physical change
(B) It undergoes a chemical change
(C) A new substance is formed
(D) It becomes a different chemical element
Answer: (A) It undergoes a physical change
19. What happens when paper is burned?
(A) New substances such as ash and gases are formed
(B) Only the size of the paper changes
(C) The paper can easily be changed back into its original form
(D) No new substance is formed
Answer: (A) New substances such as ash and gases are formed
20. Which of the following pairs contains only physical changes?
(A) Melting ice and tearing paper
(B) Burning paper and rusting iron
(C) Cooking food and burning wood
(D) Curdling milk and rusting iron
Answer: (A) Melting ice and tearing paper
21. Which of the following pairs contains only chemical changes?
(A) Burning paper and rusting iron
(B) Melting ice and freezing water
(C) Cutting paper and folding cloth
(D) Breaking glass and dissolving sugar
Answer: (A) Burning paper and rusting iron
22. Why is dissolving sugar in water generally considered a physical change?
(A) No new substance is formed and the sugar can be recovered
(B) A completely new substance is formed
(C) Sugar burns during the process
(D) Water changes into a gas
Answer: (A) No new substance is formed and the sugar can be recovered
23. Which of the following is an example of a chemical change in living organisms?
(A) Digestion of food
(B) Cutting hair
(C) Blinking of eyes
(D) Changing body position
Answer: (A) Digestion of food
24. A student observes bubbles and a temperature change when two substances are mixed. What might this indicate?
(A) A chemical reaction may have occurred
(B) Only the shape has changed
(C) The substances have simply been moved
(D) No change has occurred
Answer: (A) A chemical reaction may have occurred
25. Which statement best distinguishes physical and chemical changes?
(A) A physical change generally does not form a new substance, whereas a chemical change results in the formation of one or more new substances
(B) Physical and chemical changes are exactly the same
(C) A physical change always forms a new substance
(D) A chemical change only changes the shape of a substance
Answer: (A) A physical change generally does not form a new substance, whereas a chemical change results in the formation of one or more new substances
