Physical Changes

Q.

4. Dissolving salt in a water is a:

1. Physical change

2. Chemical change

3. Irreversible

4. All of these

Q. Water droplets formed on a cold water bottle is a physical change.

1. True
2. False

Q.

Melting of ice is a physical change or chemical change?

Q. A cold water bottle is taken out from the refrigerator. After some time, tiny water droplets formed on the bottle. Identify the change involved.

1. Physical
2. Chemical
3. Permanent
4. Periodic

Q.

Classify the following as physical or chemical change.

Making cheese from milk.

Q.

Classify the following as chemical or physical changes: Dissolving common salt in water.

Q.

What are the characteristics of physical change?

Q.

During freezing, the temperature remains constant.

1. True
2. False

Q.

The interconversion of a substance from one state of matter to another is an example of ___ change (physical/chemical).

Q.

3. Classify the following as physical change or chemical change.

(b) Glowing of an electric bulb

Q.

Find the odd one out.

1. Curdling of milk,

2. Boiling water

3. Baking bread

4. Frying chips

Q.

Classify the following change as chemical and physical change:

Dissolving common salt in water

Q.

Justify: “Melting of wax is a physical change”.

Q.

Give one word or a phrase for each of the following.

3. A change in which no new substances are formed.

Q. State whether the following statements are true or false.​
1: Cutting a log of wood into pieces is a chemical change.​
2: Formation of manure from leaves is a physical change.
3: Condensation of steam is not a chemical change.

1. 1 - False, 2 - True, 3 - True
2. 1 - False, 2 - False, 3 - True
3. 1 - True, 2 - False, 3 - True
4. 1 - True, 2 - False, 3 - False

Q.

Give main points of differences between physical and chemical changes

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

1. Heating of wax
2. Rusting of iron
3. Heating of limestone
4. Burning of candle

Q.

Classify the following processes into physical or chemical changes:

(i) Beating of aluminium metal to make aluminium foil.
(ii) Digestion of food.
(iii) Cutting of a log of wood into pieces.
(iv) Rusting of iron.

Q.

Rusting of iron is a physical change.

1. True
2. False

Q.

Statements given below are incorrect. Write the correct statements:

During a physical change new products are formed.

Q. Statement 1: No New substance is formed during a physical change.

Statement 2: New substances are formed during chemical changes.

1. Only statement 2 is true.
2. Both statements are false.
3. Both statements are true.
4. Only statement 1 is true.

Q. A change in the physical state can be brought about:

1. without any energy change
2. only when energy is taken out from the system
3. only when energy is given to the system
4. when energy is either given to, or taken out from the system

Q. The interconversion of a substance from one state of matter to another is an example of ___ change (physical/chemical).

1. Chemical
2. Physical

Q. A cold water bottle is taken out from the refrigerator. After some time, tiny water droplets are formed on the bottle. Identify the change involved.

1. Physical
2. Chemical
3. Permanent
4. Periodic