A. Answer the following questions in short:
1. To walk through a waterlogged area, you usually shorten the length of your dress by folding it. Can this change be reversed?
2. You accidently dropped your favourite toy and broke it. This is a change you did not want. Can this change be reversed?
3. A drawing sheet changes when you draw a picture on it. Can you reverse this change?
4. Give examples to explain the difference between changes that can or cannot be reversed.
5. A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilized. Can the change in POP be reversed? Why?
6. A bag of cement lying in the open gets wet due to rain during the night. The next day the sun shines brightly. Do you think the changes which have occurred in the cement, could be reversed?
7. Describe a reversible change that you can bring about by heating.
8. What do you understand by expansion and contraction? How all the three states are related to them?
9. How does a blacksmith change a piece of iron into different tools?
- CBSE Worksheets for Class 6 Science Changes Around Us Assignment 1
- CBSE Worksheets for Class 6 Science Changes Around Us Assignment 2
- CBSE Worksheets for Class 6 Science Changes Around Us Assignment 3
- CBSE Worksheets for Class 6 Science Changes Around Us Assignment 4
- CBSE Worksheets for Class 6 Science Changes Around Us Assignment 5
B. Some changes are listed in the following table. For each change, write in the blank column whether the change can be reversed or not:
C. Tick (œ“) the Correct Option:
1. …………. is not an example of chemicai change.
(a) Burning of paper
(b) Melting of wax
(c) Ripening of mango
(d) Cooking of food
2. In a physical change:
(a) shape and colour of the substance may change
(b) composition of the substance does not change
(c) no new substance is formed
(d) all of the above
3. Heat can change:
(a) state of an object
(b) size of an object
(c) solubility of a substance
(d) all of these
4. Which of the following involves a fast chemical change?
(a) The growth of a plant
(b) The rusting of iron
(c) The ripening of a mango
(d) The burning of a matchstick
5. Which of the following is an example of non-periodic change?
(b) Motion of a swing
(c) Movement of a pendulum
(d) Formation of day and night
6. The figures given below, show examples of
Fig. A Changes in chocolate state
Fig. B Changes in bulb due to electric current
(a) Both ‘A’ and lB’ are irreversible changes yA
(b) Both ‘A’ and ‘B’ are reversible changes
(c) A’ is irreversible but ‘FT is reversible change
(d) ‘A’ is reversible but4B’ is irreversible change
D. Fill in the Blanks:
1. Many materials expand on being ………………. .
2. On being heated, a gas expands …………… than a solid does.
3. Periodic changes occur after regular ……………… .
4. Breaking ice-cube into two pieces is a …………….. change.
5. Irreversible changes are ………………. in nature.
E. State True or False:
1. Every change has some cause. …………………….
2. Gases contract on cooling. ……………….
3. Cooking of rice is a physical change. ………………
4. Breaking of a China dish is a chemical change. …………….
5. Formation of clouds is a fast change. ………………
F. Match the following:
|1. Rain on a hot day||a. Chemical change|
|2. Beating of human heart||b. Physical change|
|3. Formation of day and night||c. Desirable change|
|4. Rusting of iron||d. Periodic change|
|5. Melting of ice||e. Natural change|
G. Some common changes are given in Table below. Which of these changes, do you think can be reversed?
|Change||Can be reversed Yes/No|
|Raw egg to boiled egg|
|Batter to idli|
|Wet clothes to dry clothes|
|Woollen yarn to knitted sweater|
|Grain to its flour|
|Cold milk to hot milk|
|Straight string to coiled string|
|Bud to flower|
|Milk to paneer|
|Cow dung to biogas|
|Stretched rubber band to its normal size|
|Ice cream to molten ice cream|
H. Observe preparation of disher at your home. Identify two changes that can be reversed.