The following 20 Multiple Choice Questions (MCQ) are based on
Chapter 7: Particulate Nature of Matter from the NCERT Class 8
Science textbook Curiosity. Each question has four options - select the
best answer and click to check.
Instructions: Read each question carefully. Choose the most
appropriate option from (a), (b), (c), or (d). Click
Show Answer to reveal the correct answer with explanation.
Multiple Choice Questions
1Matter is made up of:
(a) Tiny particles
(b) Only visible grains
(c) Continuous material with no particles
(d) Light rays only
(a) is correct
Even a fine speck of a substance contains particles much smaller than we can see.
2Grinding chalk into powder is a physical change because:
(a) Chalk becomes a gas
(b) Its particles stop existing
(c) Its chemical composition changes
(d) No new substance is formed
(d) is correct
Only the size of the chalk pieces changes; the substance remains chalk.
3Which observation supports the idea that matter has spaces between particles?
(a) Light forms shadows
(b) A magnet attracts iron
(c) Sugar dissolves in water without a large rise in volume
(d) A stone has mass
(c) is correct
Sugar particles fit into spaces among water particles.
4The smell of perfume spreading through a room shows that particles:
(a) Cannot mix
(b) Are continuously moving
(c) Have no spaces
(d) Exist only in solids
(b) is correct
Moving gas particles intermix and carry the smell throughout the room.
5Which state has a definite shape and definite volume?
(a) Solid
(b) Liquid
(c) Gas
(d) Vapour only
(a) is correct
Strong attractions and fixed particle positions give a solid definite shape and volume.
6Particles in a solid mainly:
(a) Move freely throughout the container
(b) Remain completely motionless
(c) Have no attraction
(d) Vibrate about fixed positions
(d) is correct
Solid particles vibrate but do not normally exchange positions.
7Why are solids difficult to compress?
(a) They have no mass
(b) They contain only air
(c) Their particles are closely packed
(d) Their particles are very far apart
(c) is correct
There is little empty space available to reduce between solid particles.
8A liquid has:
(a) A fixed shape in every vessel
(b) Definite volume but no definite shape
(c) Definite shape but no volume
(d) Neither mass nor volume
(b) is correct
A liquid keeps its volume but flows to take the shape of its container.
9Liquids can flow because their particles:
(a) Can slide past one another
(b) Are fixed in a rigid pattern
(c) Have no motion
(d) Are infinitely far apart
(a) is correct
Attractive forces keep particles close while allowing them to change neighbours.
10Which state fills the entire available container?
(a) Solid
(b) Liquid at rest only
(c) Crystal
(d) Gas
(d) is correct
Gas particles move freely and spread through all available space.
11Gases are highly compressible because their particles:
(a) Have no energy
(b) Are larger than the container
(c) Have large spaces between them
(d) Are tightly fixed
(c) is correct
Pressure can push widely separated gas particles closer together.
12Compared with a solid, attractive forces between particles of a gas are generally:
(a) Infinite
(b) Much weaker
(c) Much stronger
(d) Exactly identical in effect
(b) is correct
Weak attraction allows gas particles to move independently over large distances.
13Diffusion occurs fastest in:
(a) Gases
(b) Solids
(c) All states at exactly the same rate
(d) A vacuum without particles
(a) is correct
Gas particles move rapidly and have large interparticle spaces.
14Ink slowly spreading through still water is an example of:
(a) Freezing
(b) Grinding
(c) Magnetism
(d) Diffusion
(d) is correct
Random particle motion gradually mixes ink and water.
15Heating a substance generally makes its particles:
(a) Become massless
(b) Stop colliding
(c) Move faster
(d) Lose all motion
(c) is correct
Thermal energy increases particle motion.
16Why does diffusion usually become faster at higher temperature?
(a) Matter loses mass
(b) Particles have greater kinetic energy
(c) Particles become larger
(d) Interparticle spaces vanish
(b) is correct
Faster-moving particles intermingle more rapidly.
17When ice melts, its particles:
(a) Gain freedom to move past one another
(b) Disappear
(c) Change into a new element
(d) Lose all energy
(a) is correct
Heating weakens the fixed arrangement so liquid water can flow.
18When water vapour condenses, particles:
(a) Move infinitely far apart
(b) Become a different substance
(c) Lose their mass
(d) Come closer as energy is removed
(d) is correct
Cooling reduces motion and allows attractions to bring particles closer into a liquid.
19Air adds weight to an inflated balloon because air:
(a) Has no particles
(b) Cancels gravity
(c) Is matter and has mass
(d) Is only empty space
(c) is correct
Air consists of particles with mass, so adding air increases the balloon's total mass.
20Which order shows increasing interparticle space?
(a) Solid - gas - liquid
(b) Solid - liquid - gas
(c) Gas - liquid - solid
(d) Liquid - gas - solid
(b) is correct
Particles are generally closest in solids, farther apart in liquids and most separated in gases.
