Class 7 Science Chapter 5 Changes Around Us: Physical and Chemical worksheet with MCQs, short answer questions, practice questions and extra questions based on the NCERT Curiosity textbook for revision and exam preparation.
Class 7 Science
Chapter 5: Changes Around Us
Physical and Chemical Changes – Practice Worksheet
Name:
________________
________________
Class & Section:
________________
________________
Date:
________________
________________
Section A – Multiple Choice Questions
1. Which of the following is a physical change?
2. Which statement is correct about a physical change?
3. Which of the following is a chemical change?
4. Rust is mainly:
5. Which gas is produced when baking soda reacts with vinegar?
6. Lime water turns milky when carbon dioxide is passed through it because:
7. The burning of magnesium ribbon produces:
8. The minimum temperature at which a substance catches fire is called:
9. Which of the following is NOT a part of the fire triangle?
10. Which change involves both physical and chemical changes?
Section B – Fill in the Blanks
1. A change in which no new substance is formed is called a __________ change.
2. A change in which a new substance is formed is called a __________ change.
3. Rusting of iron is a __________ change.
4. The chemical name of rust is mainly __________.
5. Burning of a substance in the presence of oxygen is called __________.
6. The gas that turns lime water milky is __________.
7. The minimum temperature required for a substance to catch fire is called its __________ temperature.
8. Fuel, oxygen and heat together form the __________ triangle.
Section C – True or False
| Statement | True / False |
|---|---|
| 1. Melting of ice is a chemical change. | ________________ |
| 2. Rusting of iron produces a new substance. | ________________ |
| 3. Condensation of water vapour is a physical change. | ________________ |
| 4. Burning magnesium ribbon is a chemical change. | ________________ |
| 5. Baking soda and vinegar produce carbon dioxide. | ________________ |
| 6. Cutting paper always produces a new substance. | ________________ |
| 7. Decomposition of leaves into compost is a chemical change. | ________________ |
| 8. A candle shows only a physical change when it burns. | ________________ |
Section D – Identify the Type of Change
Write Physical Change, Chemical Change, or Both.
| Change | Type of Change |
|---|---|
| 1. Melting of ice | ________________________ |
| 2. Burning of wood | ________________________ |
| 3. Folding paper | ________________________ |
| 4. Rusting of iron | ________________________ |
| 5. Curdling of milk | ________________________ |
| 6. Cutting vegetables | ________________________ |
| 7. Ripening of fruits | ________________________ |
| 8. Boiling water | ________________________ |
| 9. Burning of a candle | ________________________ |
| 10. Making popcorn from corn | ________________________ |
Section E – Reversible or Irreversible?
Write Reversible or Irreversible.
| Change | Answer |
|---|---|
| 1. Melting ice | ________________ |
| 2. Burning paper | ________________ |
| 3. Folding a paper | ________________ |
| 4. Rusting of iron | ________________ |
| 5. Boiling water | ________________ |
| 6. Curdling of milk | ________________ |
| 7. Rolling a mat | ________________ |
| 8. Ripening of fruits | ________________ |
| 9. Dissolving sugar in water | ________________ |
| 10. Burning magnesium ribbon | ________________ |
Section F – Match the Following
| Column A | Column B |
|---|---|
| 1. Rusting | a. Magnesium oxide |
| 2. Burning magnesium | b. Carbon dioxide |
| 3. Vinegar + baking soda | c. Iron oxide |
| 4. Fire triangle | d. Physical and chemical changes |
| 5. Burning candle | e. Fuel, oxygen and heat |
| 6. Lime water | f. Calcium carbonate formation |
Answers: 1. ______ 2. ______ 3. ______ 4. ______ 5. ______ 6. ______
Section G – Answer in One or Two Sentences
1. What is a physical change?
2. What is a chemical change?
3. Why is rusting called a chemical change?
4. What happens when carbon dioxide is passed through lime water?
5. What is ignition temperature?
6. What are the three things required for fire?
Section H – Give Reasons
1. Rusting of iron is a chemical change.
2. Melting of ice is a physical change.
3. Lime water turns milky when carbon dioxide is passed through it.
4. A candle goes out when covered with a glass tumbler.
5. Burning of a candle involves both physical and chemical changes.
Section I – Application Based Questions
1. Riya puts an ice cube in a glass. After some time, the ice becomes water.
(a) What type of change has taken place? (b) Is a new substance formed? (c) Can the change be reversed?
(a) What type of change has taken place? (b) Is a new substance formed? (c) Can the change be reversed?
2. Aman leaves an iron nail outside in rainy weather for several days. A reddish-brown coating appears on the nail.
(a) Name the change. (b) What is the reddish-brown substance? (c) Is this change physical or chemical?
(a) Name the change. (b) What is the reddish-brown substance? (c) Is this change physical or chemical?
3. A student adds baking soda to vinegar. Bubbles are produced. The gas is passed through lime water and the lime water turns milky.
(a) Which gas is produced? (b) What does the milky appearance of lime water show? (c) Is the reaction a physical or chemical change?
(a) Which gas is produced? (b) What does the milky appearance of lime water show? (c) Is the reaction a physical or chemical change?
4. A burning candle is covered with a glass tumbler. After some time, the flame goes out.
(a) Why does the flame go out? (b) Which gas is needed for burning? (c) What happens to the available oxygen inside the tumbler?
(a) Why does the flame go out? (b) Which gas is needed for burning? (c) What happens to the available oxygen inside the tumbler?
Section J – Think and Answer
1. A piece of paper is folded into a boat. Is it a physical or chemical change? Explain.
2. Why is making curd from milk considered a chemical change?
3. A candle contains wax. When the candle burns, some wax melts and some wax vapour burns. Explain why both physical and chemical changes occur.
4. Why can a fire be stopped by removing any one part of the fire triangle?
Section K – Challenge Questions
1. A student says, “Every irreversible change is a chemical change.” Do you agree? Give an example to support your answer.
2. Soil formation from rocks may involve both physical and chemical changes. Explain.
3. Why is decomposition of plant and animal matter useful for the environment?
Answer Key
Section A – MCQs
1. (c) Melting of ice
2. (b) No new substance is formed
3. (c) Rusting of iron
4. (b) Iron oxide
5. (c) Carbon dioxide
6. (b) Calcium carbonate is formed
7. (a) Magnesium oxide
8. (c) Ignition temperature
9. (d) Water
10. (a) Burning of a candle
Section B – Fill in the Blanks
1. Physical
2. Chemical
3. Chemical
4. Iron oxide
5. Combustion
6. Carbon dioxide
7. Ignition
8. Fire
Section C – True or False
1. False
2. True
3. True
4. True
5. True
6. False
7. True
8. False
Section D – Type of Change
1. Physical
2. Chemical
3. Physical
4. Chemical
5. Chemical
6. Physical
7. Chemical
8. Physical
9. Both
10. Chemical
Section E – Reversible / Irreversible
1. Reversible
2. Irreversible
3. Reversible
4. Irreversible
5. Reversible
6. Irreversible
7. Reversible
8. Irreversible
9. Reversible
10. Irreversible
Section F – Match the Following
1. c
2. a
3. b
4. e
5. d
6. f
Section G – Short Answers
1. A physical change is a change in which no new substance is formed.
2. A chemical change is a change in which one or more new substances are formed.
3. Rusting forms a new substance called iron oxide, so it is a chemical change.
4. Lime water turns milky because calcium carbonate is formed.
5. Ignition temperature is the minimum temperature at which a substance catches fire.
6. Fuel, oxygen and heat.
Section I – Application Based
1. Physical change; no new substance is formed; yes, it can be reversed by freezing.
2. Rusting; iron oxide; chemical change.
3. Carbon dioxide; it shows the presence of carbon dioxide; chemical change.
4. The oxygen supply becomes insufficient; oxygen; the available oxygen is gradually used up.
Section K – Challenge
1. No. Some physical changes may be difficult to reverse, such as tearing paper.
2. Rocks may break physically and may also undergo chemical changes due to water and other substances.
3. Decomposition helps convert dead matter into useful nutrients and supports soil formation.
1. (c) Melting of ice
2. (b) No new substance is formed
3. (c) Rusting of iron
4. (b) Iron oxide
5. (c) Carbon dioxide
6. (b) Calcium carbonate is formed
7. (a) Magnesium oxide
8. (c) Ignition temperature
9. (d) Water
10. (a) Burning of a candle
Section B – Fill in the Blanks
1. Physical
2. Chemical
3. Chemical
4. Iron oxide
5. Combustion
6. Carbon dioxide
7. Ignition
8. Fire
Section C – True or False
1. False
2. True
3. True
4. True
5. True
6. False
7. True
8. False
Section D – Type of Change
1. Physical
2. Chemical
3. Physical
4. Chemical
5. Chemical
6. Physical
7. Chemical
8. Physical
9. Both
10. Chemical
Section E – Reversible / Irreversible
1. Reversible
2. Irreversible
3. Reversible
4. Irreversible
5. Reversible
6. Irreversible
7. Reversible
8. Irreversible
9. Reversible
10. Irreversible
Section F – Match the Following
1. c
2. a
3. b
4. e
5. d
6. f
Section G – Short Answers
1. A physical change is a change in which no new substance is formed.
2. A chemical change is a change in which one or more new substances are formed.
3. Rusting forms a new substance called iron oxide, so it is a chemical change.
4. Lime water turns milky because calcium carbonate is formed.
5. Ignition temperature is the minimum temperature at which a substance catches fire.
6. Fuel, oxygen and heat.
Section I – Application Based
1. Physical change; no new substance is formed; yes, it can be reversed by freezing.
2. Rusting; iron oxide; chemical change.
3. Carbon dioxide; it shows the presence of carbon dioxide; chemical change.
4. The oxygen supply becomes insufficient; oxygen; the available oxygen is gradually used up.
Section K – Challenge
1. No. Some physical changes may be difficult to reverse, such as tearing paper.
2. Rocks may break physically and may also undergo chemical changes due to water and other substances.
3. Decomposition helps convert dead matter into useful nutrients and supports soil formation.
Class 7 Science Changes Around Us WorksheetChanges Around Us Physical and Chemical WorksheetClass 7 Science Chapter 5 Practice WorksheetClass 7 Science Curiosity WorksheetNCERT Class 7 Science WorksheetClass 7 Science Chapter 5 QuestionsChanges Around Us Class 7 QuestionsClass 7 Science Worksheet with AnswersClass 7 Science Revision WorksheetNCERT Curiosity Chapter 5 Worksheet