Ch -1 Matter class 6,

Matter – Exercise Questions

Objective Questions (MCQs)

1. ____ have definite volume.
a) Solids
b) Liquids
c) Gases
d) Both solids and liquids

Answer: d) Both solids and liquids

2. Which of the following is a liquid at room temperature?
a) Iron
b) Silver
c) Gold
d) Mercury

Answer: d) Mercury

3. Which of the following is not an element?
a) Sodium
b) Chlorine
c) Ferrum
d) Water

Answer: d) Water

4. Particles in ____ vibrate at their fixed positions.
a) Solids
b) Liquids
c) Gases
d) Both solids and liquids

Answer: a) Solids

5. The intermolecular forces of attraction are strongest in ____.
a) Solids
b) Liquids
c) Gases
d) Both solids and liquids

Answer: a) Solids

Fill in the blanks

1. ____ is the feel of a material on touching it.

Answer: Texture

2. The particles in gaseous state quickly change their ____.

Answer: Position

3. A liquid takes the ____ of the container in which it is kept.

Answer: Shape

4. The particles of gases have ____ space between their particles.

Answer: Largest

5. The smallest particle of a compound that exhibits the same properties as the compound is ____.

Answer: Molecule

True or False

1. A silk sari has a smooth texture.

Answer: True

2. Elements are made up of same type of atoms.

Answer: True

3. Liquids have a definite volume.

Answer: True

4. Gases have weak forces of attraction between the particles.

Answer: True

5. Particles are tightly packed in liquids.

Answer: False (they are loosely packed)

Match the following

1. Metals → ____
2. Water → ____
3. Air → ____
4. Petrol → ____
5. Atom → ____

1 → c. Mostly solid
2 → a. Exists in three states
3 → d. Made up of gases
4 → b. Liquid 
5 → e. Smallest indivisible particle

Subjective Questions

1. Compare the properties of solids, liquids and gases.

Solids: Definite shape and volume, strong intermolecular force, particles vibrate at fixed positions.
Liquids: Definite volume but no fixed shape, moderate intermolecular force, particles moves within the surface 
Gases: Neither definite shape nor volume, weakest intermolecular force, particles move randomly.

2. Liquids and gases are collectively called fluids. Justify.

Liquids and gases can flow, so they are called fluids.

3. Explain atoms and molecules with the help of examples.

Atom is the smallest unit of an element (e.g., H, O).
Molecule is a group of atoms bonded together (e.g., H₂O, CO₂).

4. Differentiate between elements and compounds.

Elements: 1.Pure substances made of one kind of atom (e.g., Oxygen, Iron).2. made of atoms 
Compounds: 1.Substances formed by chemical combination of two or more elements (e.g., Water, Salt).2. made of molecules 

5. Arrange solid, liquid and gas in order of
a) increasing intermolecular forces
b) decreasing intermolecular spaces

a) Gas < Liquid < Solid
b) Gas > Liquid > Solid

Exemplar Problems

1. On stretching a spring, it changes its shape. Will you classify spring as a solid? Why?

Yes, spring is a solid because it has definite shape and volume. The change in shape is temporary (elastic).

2. Why do gases occupy the entire space available to them in the closed vessel?

Because gases have negligible intermolecular force of attraction and their particles move randomly in all directions.

3. What are the conditions necessary for something to be called as matter? Can force be called as matter?

Matter must have mass and occupy space. Force has no mass and volume, so it is not matter.

4. Water can exist in three states: solid, liquid or gas. Which state has least density? Why?

Water vapour (gas) has least density because its molecules are farthest apart.

5. State one property of liquid that solid does not possess.

Liquids can flow and take the shape of the container, unlike solids.