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Matter & Its States — Homi Bhabha Class 9 Chemistry MCQs with Solutions
Free Homi Bhabha Class 9 Chemistry Matter & Its States MCQs with step-by-step solutions covering Characteristics of Matter, Physical & Chemical States, Phase Changes & Latent Heat, Element, Compound & Mixture, Separation Techniques. Practise online on Prepizo — no login needed.
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Sample questions with solutions
Q1 — Characteristics of Matter · easy · theory
Which characteristic of matter explains why gases can be compressed easily but solids cannot?
A. Solid particles are always completely at rest
B. Gas particles are much heavier than solid particles
C. The particles of a gas have large spaces between them ✓ Correct
D. Gases have no mass while solids do
Solution: Gases have large inter-particle spaces, so the particles can be pushed closer together; in solids the particles are tightly packed with almost no space, so they resist compression.
Q2 — Characteristics of Matter · easy · theory
The gradual mixing of the particles of two different gases into one another on their own is called
A. evaporation
B. sublimation
C. diffusion ✓ Correct
D. condensation
Solution: Diffusion is the spontaneous intermixing of particles of two substances because of their continuous random motion; no stirring is needed.
Q3 — Phase Changes & Latent Heat · easy · theory
The change of a solid directly into vapour without first becoming a liquid is called
A. fusion
B. sublimation ✓ Correct
C. freezing
D. condensation
Solution: Sublimation is the direct solid-to-gas change, seen in substances such as camphor, naphthalene and dry ice.
Q4 — Element, Compound & Mixture · easy · theory
Which one of the following is a compound?
A. Air
B. Oxygen
C. Brass
D. Water ✓ Correct
Solution: Water (H2O) is a compound made of hydrogen and oxygen combined in a fixed ratio. Oxygen is an element, while air and brass are mixtures.
Q5 — Separation Techniques · easy · theory
Which method is most suitable to separate sand from water?
A. Filtration ✓ Correct
B. Distillation
C. Chromatography
D. Sublimation
Solution: Sand is insoluble in water, so it stays behind on the filter paper while the water passes through. This makes filtration the correct method.
Q6 — Characteristics of Matter · hard · theory
The spreading of the smell of perfume across a room is evidence that particles of matter:
A. are continuously moving ✓ Correct
B. cannot mix
C. have no space between them
D. are at rest
Solution: Diffusion of perfume shows particles are in constant random motion and mix with air particles.
Q7 — Characteristics of Matter · hard · theory
The random zig-zag motion of tiny particles suspended in a fluid, seen under a microscope, is called:
A. Brownian motion ✓ Correct
B. sublimation
C. condensation
D. diffusion
Solution: Brownian motion is the erratic movement of suspended particles caused by collisions with fast-moving fluid particles.
Q8 — Physical & Chemical States · hard · theory
Which of the following is a chemical change?
A. Burning of paper ✓ Correct
B. Breaking a glass
C. Dissolving salt in water
D. Melting of wax
Solution: Burning produces new substances (ash, gases) and is a chemical change; the others are physical.
Q9 — Physical & Chemical States · hard · theory
Which set contains ONLY chemical changes?
A. Freezing water, evaporating water, crushing a can
B. Tearing paper, breaking chalk, melting wax
C. Melting of ice, boiling of water, dissolving sugar
D. Burning of coal, souring of milk, rusting of iron ✓ Correct
Solution: Burning, souring and rusting all form new substances (chemical changes); the others are physical.
Q10 — Phase Changes & Latent Heat · hard · theory
The heat energy absorbed by a solid at its melting point to change into a liquid, without any rise in temperature, is called the:
A. latent heat of vaporisation
B. latent heat of fusion ✓ Correct
C. specific heat
D. heat of combustion
Solution: Latent heat of fusion is absorbed at constant temperature to convert solid to liquid.
Q11 — Phase Changes & Latent Heat · hard · theory
Evaporation of sweat cools our body because evaporation:
A. absorbs latent heat from the body ✓ Correct
B. produces a new substance
C. releases heat to the body
D. raises body temperature
Solution: Evaporating sweat takes latent heat of vaporisation from the skin, producing a cooling effect.
Q12 — Phase Changes & Latent Heat · hard · numerical
The heat required to melt 2 kg of ice at 0 °C (latent heat of fusion of ice = 336000 J/kg) is:
A. 674 J
B. 672000 J ✓ Correct
C. 168000 J
D. 336000 J
Solution: Heat $Q = mL = 2 \times 336000 = 672000$ J.
Q13 — Element, Compound & Mixture · hard · theory
A compound differs from a mixture because in a compound the components are:
A. physically mixed in any ratio
B. easily separated by filtration
C. chemically combined in a fixed ratio ✓ Correct
D. always metals
Solution: A compound has elements chemically bonded in a fixed proportion, with properties different from its constituents.
Q14 — Element, Compound & Mixture · hard · theory
When iron and sulphur are heated together to form iron sulphide, the product:
A. can be separated by a magnet
B. is a mixture
C. has properties different from both iron and sulphur ✓ Correct
D. still behaves like iron and sulphur separately
Solution: Iron sulphide is a compound whose properties differ from those of iron and sulphur (which can no longer be magnetically separated).
Q15 — Separation Techniques · hard · theory
Two miscible liquids with different boiling points (e.g. water and alcohol) are best separated by:
A. filtration
B. decantation
C. hand-picking
D. distillation ✓ Correct
Solution: Distillation vaporises the more volatile liquid, which is then condensed and collected separately.
Q16 — Separation Techniques · hard · theory
The technique used to separate the different coloured dyes present in ink is:
A. filtration
B. winnowing
C. chromatography ✓ Correct
D. evaporation
Solution: Chromatography separates components (dyes) that travel different distances on a medium.
Q17 — Separation Techniques · hard · theory
A mixture of common salt and camphor is best separated by:
A. magnetic separation
B. filtration
C. decantation
D. sublimation ✓ Correct
Solution: Camphor sublimes on heating and can be collected, while the salt is left behind.
Q18 — Characteristics of Matter · hard · theory
Assertion: The diffusion of copper sulphate through water becomes faster when the water is warm. Reason: Raising the temperature increases the kinetic energy and hence the speed of the particles. Choose the correct option.
A. Both assertion and reason are true but the reason does not explain the assertion
B. Both assertion and reason are true and the reason correctly explains the assertion ✓ Correct
C. The assertion is false but the reason is true
D. The assertion is true but the reason is false
Solution: Higher temperature gives particles more kinetic energy, so they move faster and intermix (diffuse) more quickly. The reason is the correct explanation of the faster diffusion.
Q19 — Physical & Chemical States · hard · theory
A student lists four features of a chemical change: (i) a new substance is formed, (ii) it is usually difficult to reverse, (iii) energy is often absorbed or released, (iv) only the state of matter changes. Which listed feature is WRONG for a chemical change?
A. Feature (iv) ✓ Correct
B. Feature (ii)
C. Feature (i)
D. Feature (iii)
Solution: Feature (iv), a change in state only, describes a physical change. In a chemical change a new substance forms, it is usually hard to reverse, and energy is often exchanged.
Q20 — Phase Changes & Latent Heat · hard · numerical
How much heat is required to completely melt 200 g of ice at 0 degrees C into water at 0 degrees C? (Latent heat of fusion of ice = 336 J/g)
A. 1680 J
B. 336 J
C. 6720 J
D. 67200 J ✓ Correct
Solution: Heat = mass x latent heat of fusion = 200 g x 336 J/g = 67200 J.
Q21 — Phase Changes & Latent Heat · hard · numerical
The latent heat of vaporisation of water is 2260 J/g and the latent heat of fusion of ice is 336 J/g. The heat needed to turn 50 g of water at 100 degrees C into steam at 100 degrees C is about how many times the heat needed to melt 50 g of ice at 0 degrees C?
A. about 5 times
B. about 3 times
C. about 7 times ✓ Correct
D. about 11 times
Solution: Vaporisation heat = 50 x 2260 = 113000 J; fusion heat = 50 x 336 = 16800 J. The ratio 113000 / 16800 is about 6.7, which rounds to roughly 7 times.
Q22 — Element, Compound & Mixture · hard · numerical
Water always contains hydrogen and oxygen combined in the fixed mass ratio 1:8. When 36 g of water is completely decomposed, the masses of hydrogen and oxygen obtained are
A. 8 g of hydrogen and 28 g of oxygen
B. 18 g of hydrogen and 18 g of oxygen
C. 4 g of hydrogen and 32 g of oxygen ✓ Correct
D. 32 g of hydrogen and 4 g of oxygen
Solution: In the ratio 1:8 the total is 9 parts = 36 g, so 1 part = 4 g. Hydrogen = 1 x 4 = 4 g and oxygen = 8 x 4 = 32 g. This shows the fixed composition of a compound (law of constant proportions).
Q23 — Separation Techniques · hard · theory
Acetone (boiling point 56 degrees C) and water (boiling point 100 degrees C) are miscible with each other. The correct method to separate them, with the correct reason, is
A. A separating funnel, because the two liquids are immiscible and form layers
B. Distillation, because the two liquids have sufficiently different boiling points and acetone vaporises first ✓ Correct
C. Filtration, because acetone is insoluble and stays on the filter paper
D. Sublimation, because acetone changes directly from liquid to solid
Solution: Two miscible liquids whose boiling points differ enough are separated by distillation. On heating, acetone (lower boiling point) vaporises first and is condensed and collected, leaving water behind.
Q24 — Characteristics of Matter · medium · theory
Anything that occupies space and has mass is called:
A. energy
B. matter ✓ Correct
C. force
D. pressure
Solution: Matter is anything that has mass and occupies space (volume).
Q25 — Characteristics of Matter · medium · theory
When a spoon of sugar dissolves in water without overflowing, it shows that:
A. particles of matter have spaces between them ✓ Correct
B. water is an element
C. sugar has no mass
D. sugar disappears completely
Solution: Sugar particles fit into the spaces between water particles, so the level barely changes.
Q26 — Characteristics of Matter · medium · theory
Diffusion is fastest in:
A. liquids
B. solids
C. crystals
D. gases ✓ Correct
Solution: Gas particles move fastest and are farthest apart, so diffusion is quickest in gases.
Q27 — Characteristics of Matter · medium · theory
Solids, liquids and gases differ mainly in the:
A. number of elements they contain
B. mass of their particles
C. arrangement and movement of their particles ✓ Correct
D. colour of their particles
Solution: The three states differ in how closely packed and how freely moving their particles are.
Q28 — Physical & Chemical States · medium · theory
A change in which no new substance is formed and which is usually reversible is a:
A. chemical change
B. nuclear change
C. combustion
D. physical change ✓ Correct
Solution: Physical changes (e.g. melting, dissolving) form no new substance and are often reversible.
Q29 — Physical & Chemical States · medium · theory
The rusting of iron is an example of a:
A. physical change
B. reversible change
C. chemical change ✓ Correct
D. change of state only
Solution: Rusting forms a new substance (iron oxide), so it is a chemical change.
Q30 — Physical & Chemical States · medium · theory
Melting of ice into water is a physical change because:
A. no new substance is formed and it can be reversed by freezing ✓ Correct
B. a new substance (water) is created
C. it is irreversible
D. it releases a gas
Solution: Ice and water are the same substance in different states; freezing reverses the change.