Question

I. Fill in the blanks by select the correct the option:

1. A physical change is ___________ [temporary/permanent].

2. A chemical change is ___________ [reversible/irreversible].

3. Burning of a candle is a _________ [physical /chemical] change.

4. Melting of ice is a ___________ [physical /chemical] change.

5. A chemical change _______ [is / is not generally associated with evolution or absorption of heat.

II. Match the following:

1. Wood is burnt to ashes. A. Physical change

2. Water evaporation from the sea. B. Chemical change

3. Ann electric bulb is switched on.

4. Water is frozen to ice.

5. Green plants undergo photosynthesis.

III. State whether the statement are true or false. If false write the correct statement:

1. Water turning to steam is a physical change.

2. A new substance may or may not be formed during a chemical change.

3. Curdling of milk is considered a physical change.

4. On addition of sodium to water, hydrogen is evolved. Hence the change is physical.

5. Exposure of iron to the moist atmosphere results in a chemical change.

IV. Classify the following as physical and chemical change:

1.Ripening of fruits 15. Melting of ice

2. Liquefying of air. 16. Burning of agarbatti

3. Charging of car battery. 17. Tearing of cloth

4. Drying of wet clothes. 18. Cooking of food

5. Manufacture of salt from sea water. 19. Formation of cloud

6. Making of curd from milk. 20. Formation of seed from flower.

7. Butter getting rancid. 21. Burning of cooking gas.

8. Heating of platinum wire. 22. Dissolution of sugar in water.

9. Growth of a tree. 23. Melting of butter.

10. Rusting of iron. 24. Lightning in the sky.

11. Making of dry ice from CO2. 25. Explosion of fire crackers.

12. Bursting of water pipes in severe cold.

13. Boiling of water.

14. Burning of paper.

V. Give reason why the following are considered as physical changes:

1. An iron is magnetized.

2. Butter is melted.

3. A fruit is dried.

4. Iron expands on heating.

5. Carbon dioxide is liquefied to give liquid carbon dioxide.​

Answer 1

Answer:

I.

1.temporary

2.irreversible

3.both physical and chemical change happens.

4.physical

5.is

solved only first question.............

hope it helps......