Physical and chemical changes Worksheet-3

Physical and chemical changes Worksheet-3

Multiple-Choice Question:

1. When a new substance is formed with different properties than the original substance, it is called a

(A) Physical change                        

(B) Chemical change

(C) Both of these

2. Which of the following is an example of chemical change?

(A) Freezing of water                      (B) Cutting of wood

(C) Baking of bread                         (D) Bending of wire

3. Two solutions are mixed together and the new solution thus formed is very hot. This observation tells us that:

(A) A chemical change is taking place

(B) A gas is being produced

(C) The solutions are not soluble

(D) The physical properties are the same

4. Which of the following statement is correct?

(A) Crystallization is a chemical change

(B) Digestion is a chemical change

(C) Burning of paper is a temporary change

(D) A chemical change is always reversible

5. prevent rusting?

(A) Painting                                      (B) Greasing

(C) Galvanization                            (D) Precipitation

6. Change in colour of sliced Potato & Brinjal is a:

(A) Physical change                        

(B) Chemical change

(C) Both of these

7. Heating an iron nail is a:

(A) Physical change                        

(B) Chemical change

(C) None of these

8. Breaking of ozone is a:

(A) Physical change                        

(B) Chemical change

(C) Both of these

9. A mixture of cement, sand, and water hardens into concrete and heat is released. It is a:

(A) Physical change                        

(B) Chemical change

(C) Both of these

10. The metal in a car exposed to salt and water slowly crumbles into tiny pieces. It is a:

(A) Physical change                        

(B) Chemical change

(C) Both of these

11. Food scraps decomposing in a compost heap is a:

(A) Physical change                        

(B) Chemical change

(C) None of these

True of False:

12. Burning a piece of wood to form ash is a physical change.
13. Conversion of water into steam is a physical change.
14. Cutting a piece of cork into half is a physical change.
15. Absorption of water by a paper towel is a chemical change.
16. Rotting of an apple is a chemical change.
17. Inflation of a tyre with air is a chemical change.
18. Conversion of sunlight, CO2 and water into sugar and oxygen during the process of photosynthesis is a physical change.
19. Dissolution of sugar in water is a physical change.
20. Preparation of an omelette from eggs is a physical change.
21. Melting of an ice cube is a physical change.
22. Cutting of log of wood into small pieces is a physical change.
23. Stretching a rubber band is a physical change.

Answer key:

1. (B)
2. (C)
3. (A)
4. (B)
5. (C)
6. (B)
7. (A)
8. (B)
9. (C)
10. (C)
11. (B)
12. False
13. True
14. True
15. False
16. True
17. False
18. False
19. True
20. True
21. True
22. True
23. True