Fast and Slow Changes

Q.

What is the meaning of periodic change? Give examples.

Q.

Give examples to explain the difference between changes that can or cannot be reversed.

Q.

A sheet of paper is used to make a paper boat. This is a:

1. physical and temporary

2. chemical and temporary

3. reversible and permanent

4. irreversible and temporary

Q.

While lighting a candle, Paheli observed the following changes. (i) Wax was melting (ii) Candle was burning (iii) Size of the candle was reducing (iv) Melted wax was getting solidified Of the above, the changes that can be reversed are

1. (i) and (ii)

2. (ii) and (iii)

3. (iii) and (iv)

4. (i) and (iv)

Q. An iron ring is heated. Which of the following statements is incorrect for the given iron ring?

1. The change occurring in this case is reversible
2. The ring expands
3. The shape of the ring changes and the change is irreversible
4. The ring comes to the same size upon cooling

Q.

Which among the following is/are example of reversible change?

1. Making structures of sand on beach

2. Making egg omlett

3. Burning gasoline

4. Cutting of trees

Q.

Melting of ice cream is a:-

1. Reversible, Physical and Permanent

2. Reversible, Physical and Temporary

3. Irreversible, Physical and Temporary

4. Chemical, Irreversible and Temporary

Q.

Germination of seeds is a _____________ (periodic/desirable) change.

Q.

Which of the following is an example of reversible change?

1. Molding clay to form a toy.

2. Making a light mark on a paper with a pencil.

3. Cutting a piece of paper.

4. Ripening of fruits.

Q.

A child came to see Aristotle and talked about dry leaves falling in his courtyard. The child was delighted with the beauty of nature. This made him think that what kind of change is this?

1. This is a reversible change

2. This isn't a reversible change

3. This isn't change

4. This can't be classified among reversible or irreversible change

Q.

Ram was given a piece of paper and was asked to make a paper plane. What kind of a change does the paper undergo?

Q.

Which of the following is a reversible change?

1. Milk turning sour

2. Burning of wax in a candle

3. Melting of wax

4. Cooking a vegetable

Q.

Differentiate between periodic and non-periodic changes.

Q.

Bharath heated a closed vessel full of water. After some time he observed that the water started boiling and after some more time there is no water in the vessel. This is an example of___change. (reversible/irreversible)

Q.

Give one example of slow and fast changes.

Q.

1. Few children were inflating balloons.
2. Farmers were harvesting crops in their fields.

Among the aforementioned observations, which are the examples of reversible change?

1. Only observation 1 is a reversible change.

2. Only observation 2 is a reversible change.

3. Both observation 1 & observation 2 are reversible changes.

4. Both observation 1 & observation 2 are not reversible changes.

Q. Match the given changes with their type.

1. Slow change
2. Fast change
3. Periodic change

Q.

Differentiate between slow and fast changes.

Q.

5. lt was Paheli’s birthday, her brother Simba was helping her to decorate the house for the birthday party and their parents were also busy making other arrangements. Following were the activities going on at Paheli’s home:

(viii) Father fried the puries in hot oil.

Identify whether this activity can be reversed or not.

Q. Which among the following is a reversible change?

1. Formation of curd
2. Orange juice is frozen to make ice lollies.
3. Chopping off a mango into pieces
4. Baking bread.

Q.

Bharath heated a closed vessel full of water. After some time he observed that the water started boiling. Later there was no water in the vessel.

This is a/an ___.

1. chemical change.

2. reversible change.

3. irreversible change.

4. cannot be determined.

Q. Shreya drops a vase of flowers and glass scatters all over the floor. Identify the type of change depicted in the above scenario.

1. Reversible
2. Irreversible
3. Physical
4. Chemical

Q. Identify the reversible changes among the following:
Change 1 - Children inflating balloons
Change 2 - Farmers harvesting crops

1. Only 1 is a reversible change.
2. Only 2 is a reversible change.
3. Both 1 and 2 are reversible changes.
4. Neither 1 nor 2 are reversible changes.

Q.

Differentiate between the following:

Reversible and Irreversible change.

Q.

Reversible change refers to:

1. Change in which new substance is formed.

2. Change that can be undone.

3. Change that cannot be undone.

4. Change in which shape and size is changed.

Q.

The growing of a moustache over a boy's face is a reversible change.

1. True

2. False

Q.

5. Can we say ironing of cloth is reversible change? Give reason.

Q. Shreya drops a vase of flowers and glass scatters all over the floor. Identify the type of change depicted in the above scenario.

1. Chemical
2. Reversible
3. Physical
4. Irreversible

Q. The change in which the substance can be brought back into its original state is called a change.

1. permanent
2. reversible
3. irreversible

Q.

Riya observed two scenes around her. Choose the correct classification of changes for the observations.

1. Few children were inflating balloons.
2. Farmers were harvesting crops in their fields.

1. Observation 1 - Irreversible
   Observation 2 - Reversible

2. Observation 1 - Reversible
   Observation 2 - Irreversible

3. Observation 1 - Reversible
   Observation 2 - Reversible

4. Observation 1 - Irreversible
   Observation 2 - Irreversible