Observations That Indicate a Change

Q.

Is Water Boiling At 100 Degrees Celsius a Physical Or Chemical Property?

Q. Which amongst the following is not an indicator of a chemical change?

1. Evolution of gas
2. Release of heat
3. Change in smell
4. Change in shape

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

1. reversible
2. irreversible
3. permanent

Q. The characteristic nature of physical change is that the ___________ of the substance remains the same.

1. colour
2. state
3. composition
4. size

Q.

Which of the given changes are observed when sugar is heated?

1. Change in colour

2. Change in chemical composition

3. Change in shape

4. Change in physical state

Q. Which amongst the following indicators will help Sara to separate rotten eggs from good ones?

1. Change in shape
2. Change in state
3. Change in odour
4. Change in size

Q.

Which is not a mixture

1. sugar solution

2. tap water

3. milk

4. distilled water

Q.

Classify the given activities into two buckets: Change in shape and change in physical state.

(i) Crumpling paper

(ii) Cutting vegetables

(iii) Heating solid ghee

(iv) Solidification of water to ice cubes

1. Change in shape:- (i), (ii)

   Change in physical state:- (ii) , (iii)

2. Change in shape:- (iii) , (iv)

   Change in physical state:- (i) , (ii)

3. Change in shape:- (i), (ii), (iii) , (iv)

   Change in physical state:- (iii) , (iv)

4. Change in shape:- (i), (ii), (iii)

   Change in physical state:- (iii) , (iv)

Q.

The process of sublimation of a solid is a physical change.

1. True
2. False

Q.

A change may involve:

1. Change in color

2. Change in taste

3. Change in physical state, shape and size

4. All of the above

Q. Which amongst the following indicators will help Sara to separate rotten eggs from good ones?

1. Change in shape
2. Change in state
3. Change in odour
4. Change in size

Q. Tearing of paper is a change that can be undone.

1. False
2. True

Q.

Why is the liquid substance in our nose is always yellow or white, why not black or blue?

Q. Paheli had brought a new bottle of pickle from the market. She tried to open the metal cap to taste it but could not do so. She then took a bowl of hot water and immersed the upper end of the bottle in it for five minutes. She could easily open the bottle now. Can you give the reason for this?

Q. Folding of paper is a change that can be undone.

1. True
2. False

Q. The burning of paper is a reversible change.

1. False

2. True

Q. Which of the following is observed when sugar is heated?

1. Change in chemical composition
2. No change in shape
3. No change in chemical composition
4. No change in colour

Q.

7. Give one word:

5. Name the change in which there is change in state, size and shape of substance.

Q. Pick the correct pairs based on the changes and their causes.

1. Melting of iron
2. Cutting of tree
3. Human activity
4. Temperature
5. Force
6. Crushing bottle

Q.

Which of the given changes are observed when sugar is heated?

1. Change in colour

2. Change in chemical composition

3. Change in shape

4. Change in physical state

Q.

Can decolouration of the leaves in autumn be considered a change?

1. True

2. False

Q. Choose the correct pairs based on seasons and their corresponding months in India.

1. Summer
2. Winter
3. Monsoon
4. Autumn
5. September
6. December
7. March
8. June