Causes of a Change

Q. Heating or applying force cannot cause any change in a substance.

1. True
2. False

Q.

A blacksmith hammers a hot piece of iron while making a tool. How does the force due to hammering affect the piece of iron?

Q. Identify the processes used to recover both salt and water from a salt water mixture.

1. i and ii
2. i and iii
3. i and iv
4. ii and iii

Q.

1. Only statement A is correct.

2. Only statement B is correct.

3. Both A and B are correct.

4. Neither one is correct.

Q. Heating can cause a change in state of a substance.

1. False
2. True

Q. Heating of a substance can cause its expansion.

1. True
2. False

Q. In the process of ______, a solid substance absorbs heat from the surroundings.

1. condensation
2. evaporation
3. melting
4. freezing

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 following are examples of a change caused due to heating?

1. Melting of ice
2. Boiling of water
3. Cooking of food
4. Cutting of wood
5. Tearing of paper
6. Drying of cloth
7. Boiling of rice
8. Writing on paper

Q. In _____ process, water vapour is converted into water.

1. boiling
2. evaporation
3. condensation
4. precipitation

Q. Peter is evaluating two cases given below.
Case 1: Hammering of iron sheet to bend it
Case 2: Melting of wax
Identify the cause of change in both the cases.

1. Case 1: Force
   Case 2: Force
2. Case 1: Force
   Case 2: Temperature
3. Case 1: Temperature
   Case 2: Force
4. Case 1: Temperature
   Case 2: Temperature

Q. Heating or applying force cannot cause any change in a substance.

1. True
2. False