Important MCQ for CBSE Class 9 Science Chapter 1: Matter in our Surrounding

Understanding the Basics of Matter in Our Surrounding

In science, matter exists in different states: solids, liquids, gases, and plasma. Here’s a quick guide to help you understand these states and their properties:

Important MCQ for CBSE Class 8 Social Science Chapter 1: Matter in our Surrounding


1.     Gas Pressure: Gas pressure happens because the particles of the gas are constantly moving and bumping into the walls of their container.

2.     Spread of Particles: In gases, the particles are the most spread out, unlike in solids where they are packed closely together.

3.     Flow and Shape: Liquids and gases can flow and take the shape of their container, a property known as fluidity.

4.     Sponge Compression: Sponges can be easily compressed because they have air pockets inside that can be squeezed out.

5.     Closest Particles: In solids, the particles are closest together, which is why solids have a fixed shape and volume.

6.     Effect of Temperature: When you heat something, it generally spreads out and moves faster, speeding up the process of diffusion. Conversely, cooling a gas makes its particles move slower and come closer together.

7.     Heating Liquids: When a liquid is heated, it turns into gas because the particles gain energy and move faster.

8.     Gas Flexibility: Gases are unique because they can easily change shape and volume, adapting to the container they are in.

This MCQ covers the basics of how different states of matter behave and interact with changes in temperature and pressure.

CBSE Class 9 Science Chapter-1: Matter in our surrounding MCQs

1. What is matter?

A) Only solids 

B) Only liquids 

C) Everything that has mass and occupies space 

D) Only gases

Answer: C) Everything that has mass and occupies space.

Explanation: Matter is defined as anything that has mass and takes up space. This includes solids, liquids, and gases.

2. What does the activity with dissolving salt in water demonstrate about matter?

A) Matter is continuous 

B) Matter is made of particles 

C) Matter cannot dissolve 

D) Matter does not change volume

Answer: B) Matter is made of particles

Explanation: Dissolving salt in water shows that salt particles spread throughout the water, indicating that matter is made of particles that can mix and occupy the spaces between other particles.

3. Why does the smell of hot food reach you faster than the smell of cold food?

A) Hot food has more particles 

B) The particles in hot food move faster 

C) Cold food particles move faster 

D) Smell is not affected by temperature

 Answer: B) The particles in hot food move faster

Explanation: The particles in hot food move faster, which speeds up the diffusion of smell particles into the air, allowing the smell to reach you more quickly.

4. What property of matter allows a diver to move through water?

A) Rigidity 

B) Compressibility 

C) Fluidity 

D) Density

Answer: C) Fluidity

Explanation: Water is a fluid, which means it can flow and change shape, allowing a diver to move through it easily.

5. What happens to the volume of a liquid when it is transferred to different containers?

A) It changes 

B) It remains the same 

C) It becomes gas 

D) It increases

Answer: B) It remains the same

Explanation: Liquids have a fixed volume, so transferring them to different containers does not change their volume, although their shape does change to match the container.

6. Which state of matter has particles that are in constant, random motion and spread out to fill any container?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: Gas particles move randomly and quickly, spreading out to fill any container they are in.

7. Which of the following states of matter can be compressed the most easily?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: Gases can be compressed easily because their particles are far apart and move quickly, allowing them to be pushed closer together.

8. What is diffusion?

A) The mixing of gases with solids 

B) The spreading of particles from an area of high concentration to an area of low concentration 

C) The process of changing from liquid to solid 

D) The force exerted by matter

Answer: B) The spreading of particles from an area of high concentration to an area of low concentration

Explanation: Diffusion is the process where particles spread from regions of high concentration to low concentration, leading to even distribution.

9. Which of the following best describes the particles in a solid?

A) They move randomly and quickly 

B) They are tightly packed and vibrate in place 

C) They are spread out and move freely 

D) They do not interact with each other

Answer: B) They are tightly packed and vibrate in place

Explanation: In solids, particles are closely packed together and only vibrate in place, which gives solids their definite shape and volume.

10. What does the activity with ink and honey in water show about the state of matter?

A) Solids diffuse faster than liquids 

B) Liquids diffuse slower than gases 

C) Gases diffuse slower than liquids 

D) Solids and liquids have similar rates of diffusion

Answer: B) Liquids diffuse slower than gases.

Explanation: The activity shows that liquids (like ink and honey) diffuse slower than gases because particles in liquids are less free to move compared to gases.

11. Which property allows a sponge to be compressed?

A) Rigidity 

B) Density 

C) Presence of air pockets 

D) Fixed shape

Answer: C) Presence of air pockets

Explanation: A sponge can be compressed due to the air pockets within it, which get squeezed out when pressure is applied.

12. When a gas is compressed, what happens to its volume?

A) It remains the same 

B) It increases 

C) It decreases 

D) It becomes a liquid

Answer: C) It decreases

Explanation: Compressing a gas reduces its volume because the particles are forced closer together.

13. Why do solids have a definite shape and volume?

A) The particles are free to move around 

B) The particles are tightly packed and only vibrate 

C) The particles are loosely packed 

D) The particles are in constant random motion

Answer: B) The particles are tightly packed and only vibrate

Explanation: In solids, particles are tightly packed and only vibrate, which prevents the solid from changing shape or volume.

14. What happens when you try to compress a liquid?

A) Its volume decreases significantly 

B) Its volume remains nearly the same 

C) It turns into a gas 

D) It evaporates

Answer: B) Its volume remains nearly the same

Explanation: Liquids are not easily compressible, so their volume stays nearly the same when pressure is applied.

15. What is observed when a solid like sugar dissolves in water?

A) The solid remains visible 

B) The solid disappears completely from sight 

C) The solid forms a separate layer 

D) The solid mixes into the water, indicating particles in matter

Answer: D) The solid mixes into the water, indicating particles in matter

Explanation: When sugar dissolves, it mixes into the water, showing that sugar particles fit into the spaces between water particles.

16. What causes the particles in gases to exert pressure on the walls of their container?

A) The particles are tightly packed 

B) The particles move randomly and collide with the walls 

C) The particles are in a fixed position 

D) The particles are not in motion

Answer: B) The particles move randomly and collide with the walls

Explanation: In gases, particles move randomly and collide with the walls of their container, which causes the pressure.

17. In which state of matter do particles have the highest kinetic energy?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: In gases, particles have the highest kinetic energy due to their fast and random movement.

18. Which of the following can diffuse through a liquid the fastest?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: Gases diffuse the fastest because their particles move quickly and are spread out more than those in solids or liquids.

19. What happens to the smell of a perfume when you spray it in a room?

A) It stays concentrated in one spot 

B) It spreads quickly throughout the room 

C) It does not spread at all 

D) It turns into a liquid

Answer: B) It spreads quickly throughout the room

Explanation: The particles of the perfume spread quickly throughout the room due to diffusion, making the smell detectable from a distance.

20. Which of the following states of matter does NOT have a fixed shape?

A) Solid 

B) Liquid 

C) Gas 

D) All of the above

Answer: B) Liquid

Explanation: Liquids do not have a fixed shape; they take the shape of their container, but they have a fixed volume.

21. When a crystal of potassium permanganate is added to water, why does the colour spread even after several dilutions?

A) The particles are very large 

B) The particles are very small and spread throughout 

C) The colour is not affected by dilution 

D) The particles settle at the bottom

Answer: B) The particles are very small and spread throughout

Explanation: The small particles of potassium permanganate spread throughout the water even after multiple dilutions, showing that the particles are tiny and distributed widely.

22. What is the main reason for gases having low density compared to liquids and solids?

A) Gases have a higher mass 

B) Gases have particles that are far apart 

C) Gases are denser than liquids 

D) Gases do not move

Answer: B) Gases have particles that are far apart.

Explanation: In gases, particles are much farther apart compared to those in liquids and solids, which results in a lower density.

23. Why can’t you easily compress a liquid like you can with a gas?

A) Liquids are too dense 

B) Liquids have particles that are already close together 

C) Liquids do not flow 

D) Liquids have no particles

Answer: B) Liquids have particles that are already close together

Explanation: The particles in liquids are already close together, so they do not compress easily, unlike gases where particles are more spread out.

24. What does the term "kinetic energy" refer to in the context of matter?

A) The energy due to an object's position 

B) The energy due to the random movement of particles 

C) The energy required to change state 

D) The energy stored in bonds

Answer: B) The energy due to the random movement of particles

Explanation:  Kinetic energy in matter refers to the energy associated with the random movement of particles.

25. Which state of matter can be easily compressed and transported in cylinders?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: Gases can be compressed into cylinders because their particles are far apart, making them more compressible than solids or liquids.

26. What happens to the rate of diffusion when the temperature increases?

A) The rate decreases 

B) The rate remains the same 

C) The rate increases 

D) Diffusion stops

Answer: C) The rate increases

Explanation: Higher temperatures increase the kinetic energy of particles, which speeds up the rate of diffusion.

27. What is the main reason that solids have a definite shape?

A) The particles move freely 

B) The particles are tightly packed and fixed in place 

C) The particles have high kinetic energy 

D) The particles are not in contact with each other

Answer: B) The particles are tightly packed and fixed in place

Explanation: Solids have a definite shape because their particles are tightly packed and fixed in place, preventing them from changing shape.

28. In which state of matter do particles have the least kinetic energy?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: A) Solid

Explanation: In solids, particles have the least kinetic energy because they vibrate in fixed positions rather than moving freely.

29. Which state of matter flows and takes the shape of its container?

 A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: B) Liquid

Explanation: Liquids flow and take the shape of their container, but they maintain a fixed volume.

30: What does the term "diffusion" refer to in relation to gases?

A) The mixing of gases with solids 

B) The spreading of gas particles throughout a space 

C) The change of a gas into a liquid 

D) The separation of gases from each other

Answer: B) The spreading of gas particles throughout a space

Explanation: Diffusion is the process by which gas particles spread out and mix with other gases.

31. What happens when a solid is heated?

A) It melts instantly 

B) Its particles move less 

C) Its particles gain more kinetic energy 

D) It becomes a gas immediately

Answer: C) Its particles gain more kinetic energy

Explanation: Heating a solid increases the kinetic energy of its particles, causing them to vibrate more and potentially change state.

32. What is an example of a substance that has a definite volume but no definite shape?

A) Ice 

B) Water 

C) Iron 

D) Sand

Answer: B) Water

Explanation: Water has a definite volume but no definite shape; it takes the shape of its container.

33. Why can gases be compressed into small volumes?

A) The particles are close together 

B) The particles are very large 

C) The particles move quickly and are far apart 

D) The particles are fixed in place

Answer: C) The particles move quickly and are far apart

Explanation: Gases can be compressed because their particles are far apart and move quickly, allowing them to be squeezed into smaller volumes.

34. Which state of matter cannot be compressed easily?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: B) Liquid

Explanation: Liquids cannot be easily compressed because their particles are already close together.

35. When sugar is dissolved in water, what happens to the sugar particles?

A) They form a separate layer 

B) They stay visible 

C) They spread throughout the water 

D) They turn into gas

Answer: C) They spread throughout the water

Explanation: Dissolved sugar particles spread evenly throughout the water, showing the mixing of particles.

36. Which of the following states of matter has particles that are in constant random motion?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: In gases, particles are in constant random motion, which contributes to their ability to fill any container.

37. What does the term "compressibility" refer to?

A) The ability to change state 

B) The ability to dissolve in liquids 

C) The ability of a substance to be squeezed into a smaller volume 

D) The ability to maintain shape

Answer: C) The ability of a substance to be squeezed into a smaller volume

Explanation: Compressibility refers to how much a substance can be squeezed into a smaller volume.

38. How do particles in a liquid move compared to those in a solid?

A) They move more freely in a liquid 

B) They move less freely in a liquid 

C) They move in the same way 

D) They are fixed in place in a liquid

Answer: A) They move more freely in a liquid

Explanation: Particles in a liquid move more freely than those in a solid, which allows liquids to flow and change shape.

39. What is observed when a drop of ink is added to water?

A) The ink stays in one spot 

B) The ink spreads throughout the water 

C) The ink turns into a solid 

D) The water changes colour instantly

Answer: B) The ink spreads throughout the water

Explanation: The ink spreads throughout the water due to diffusion, where particles move from an area of high concentration to low concentration.

40. Why does heating a gas increase its pressure?

A) The gas particles move slower 

B) The gas particles move faster and collide more with the container walls 

C) The gas particles get further apart 

D) The gas particles dissolve in the container

Answer: B) The gas particles move faster and collide more with the container walls

Explanation: Heating a gas increases the speed of its particles, causing them to collide more with the container walls and thus increasing pressure.

41. What is an example of a substance that can exist in all three states of matter?

A) Water 

B) Iron 

C) Carbon 

D) Helium

Answer: A) Water

Explanation: Water can exist as a solid (ice), liquid (water), and gas (steam), depending on the temperature.

42. What causes the pressure exerted by a gas in a container?

A) The particles sticking to the container walls 

B) The movement of particles colliding with the container walls 

C) The temperature of the gas 

D) The density of the gas

Answer: B) The movement of particles colliding with the container walls

Explanation: Gas pressure is caused by the collisions of gas particles with the walls of their container.

43. Which state of matter has particles that are most spread out?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: In gases, particles are the most spread out compared to solids and liquids.

44. What property of matter is demonstrated by the ability to flow and take the shape of its container?

A) Solubility 

B) Compressibility 

C) Fluidity 

D) Density

Answer: C) Fluidity

Explanation: Fluidity is the property that allows a substance to flow and take the shape of its container, characteristic of liquids and gases.

45. Why does a sponge compress easily?

A) The sponge is made of liquid 

B) The sponge contains air pockets 

C) The sponge is a gas 

D) The sponge is very dense

Answer: B) The sponge contains air pockets

Explanation: The air pockets in a sponge allow it to be compressed as the air is pushed out when pressure is applied.

46. Which state of matter has particles that are closest together?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: A) Solid

Explanation: In solids, particles are closest together, giving solids their fixed shape and volume.

47. What is the effect of increasing the temperature on the diffusion rate of a substance?

A) The diffusion rate decreases 

B) The diffusion rate stays the same 

C) The diffusion rate increases 

D) Diffusion stops

Answer: C) The diffusion rate increases

Explanation: Increasing temperature increases the kinetic energy of particles, which speeds up the diffusion process.

48. When a gas is cooled, what happens to its particles?

A) They move faster 

B) They move slower and get closer together 

C) They stay the same 

D) They become more spread out

Answer: B) They move slower and get closer together

Explanation: Cooling a gas slows down its particles and causes them to move closer together.

49. What do we observe when a liquid is heated?

A) The liquid freezes 

B) The liquid turns into gas 

C) The liquid's particles slow down 

D) The liquid remains unchanged

Answer: B) The liquid turns into gas

Explanation: Heating a liquid increases the kinetic energy of its particles, which can cause it to evaporate into a gas.

50. Which state of matter has particles that can easily change shape and volume?

A) Solid 

B) Liquid 

C) Gas 

D) Plasma

Answer: C) Gas

Explanation: Gases can change both shape and volume easily due to the high movement and spread of their particles.

Previous Post Next Post