🟦 Is matter around us pure MCQs
Q.1
Which of the following is NOT a basic physical state of matter?
- (a) Solid
- (b) Gas
- (c) Plasma
- (d) Liquid
Answer: (c) Plasma
Explanation: At school level, matter is classified into solid, liquid, and gas.
Explanation: At school level, matter is classified into solid, liquid, and gas.
Q.2
Which of the following is a pure substance?
- (a) Soil
- (b) Milk
- (c) Oxygen (O2)
- (d) Soft drink
Answer: (c) Oxygen (O2)
Explanation: Oxygen is an element, hence a pure substance.
Explanation: Oxygen is an element, hence a pure substance.
Q.3
The only liquid metal at room temperature is:
- (a) Iron
- (b) Mercury
- (c) Sodium
- (d) Potassium
Answer: (b) Mercury
Explanation: Mercury (Hg) is liquid at room temperature.
Explanation: Mercury (Hg) is liquid at room temperature.
Q.4
Which property is NOT typical of metals?
- (a) Malleability
- (b) Ductility
- (c) Sonority
- (d) Brittleness
Answer: (d) Brittleness
Explanation: Brittleness is a property of non-metals.
Explanation: Brittleness is a property of non-metals.
Q.5
Which of the following is a metalloid?
- (a) Boron
- (b) Sodium
- (c) Bromine
- (d) Iron
Answer: (a) Boron
Explanation: Metalloids show properties of both metals and non-metals.
Explanation: Metalloids show properties of both metals and non-metals.
Q.6
Sodium chloride (NaCl) is a/an:
- (a) Element
- (b) Mixture
- (c) Compound
- (d) Colloid
Answer: (c) Compound
Explanation: Na and Cl combine chemically in a fixed ratio.
Explanation: Na and Cl combine chemically in a fixed ratio.
Q.7
Which one is a heterogeneous mixture?
- (a) Sugar solution
- (b) Air
- (c) Soil
- (d) Copper sulphate solution
Answer: (c) Soil
Explanation: Soil has non-uniform composition and visible parts.
Explanation: Soil has non-uniform composition and visible parts.
Q.8
Tincture of iodine is:
- (a) Iodine in water
- (b) Iodine in alcohol
- (c) Iodine in NaCl
- (d) Iodine in sugar solution
Answer: (b) Iodine in alcohol
Explanation: Used as an antiseptic solution.
Explanation: Used as an antiseptic solution.
Q.9
Which statement is NOT true for a true solution?
- (a) It is homogeneous
- (b) Cannot be separated by filtration
- (c) Particles scatter light
- (d) It is stable
Answer: (c) Particles scatter light
Explanation: Scattering is a feature of colloids and suspensions.
Explanation: Scattering is a feature of colloids and suspensions.
Q.10
A saturated solution at a given temperature means:
- (a) No more solute can dissolve
- (b) More solute can dissolve
- (c) It is dilute
- (d) It is heterogeneous
Answer: (a) No more solute can dissolve
Explanation: It contains maximum solute at that temperature.
Explanation: It contains maximum solute at that temperature.
Q.11
Which mixture certainly shows Tyndall effect?
- (a) Salt solution
- (b) Sugar solution
- (c) Colloid
- (d) None of these
Answer: (c) Colloid
Explanation: Intermediate particle size scatters light.
Explanation: Intermediate particle size scatters light.
Q.12
Which is an example of a suspension?
- (a) Milk
- (b) Muddy water
- (c) Air
- (d) Soda water
Answer: (b) Muddy water
Explanation: Visible particles that settle on standing.
Explanation: Visible particles that settle on standing.
Q.13
Milk is an example of:
- (a) Solution
- (b) Suspension
- (c) Colloid
- (d) Compound
Answer: (c) Colloid
Explanation: Fat droplets dispersed in water (emulsion).
Explanation: Fat droplets dispersed in water (emulsion).
Q.14
Dust seen in a light beam entering a room is due to:
- (a) Brownian motion
- (b) Tyndall effect
- (c) Filtration
- (d) Evaporation
Answer: (b) Tyndall effect
Explanation: Light is scattered by tiny particles.
Explanation: Light is scattered by tiny particles.
Q.15
Which is a physical change?
- (a) Rusting of iron
- (b) Burning of paper
- (c) Ice melting
- (d) Milk turning sour
Answer: (c) Ice melting
Explanation: State changes, no new substance formed.
Explanation: State changes, no new substance formed.
Q.16
Which is a chemical change?
- (a) Dissolving sugar in water
- (b) Melting of wax
- (c) Burning of wax
- (d) Boiling of water
Answer: (c) Burning of wax
Explanation: New substances (CO2 and H2O) form.
Explanation: New substances (CO2 and H2O) form.
Q.17
Burning of a candle shows:
- (a) Only physical change
- (b) Only chemical change
- (c) Both physical and chemical change
- (d) No change
Answer: (c) Both physical and chemical change
Explanation: Wax melts (physical), wax burns (chemical).
Explanation: Wax melts (physical), wax burns (chemical).
Q.18
The best method to separate salt from its solution is:
- (a) Filtration
- (b) Evaporation
- (c) Sedimentation
- (d) Decantation
Answer: (b) Evaporation
Explanation: Salt solution is homogeneous; water is removed by evaporation.
Explanation: Salt solution is homogeneous; water is removed by evaporation.
Q.19
Which is NOT a property of a suspension?
- (a) Particles visible to naked eyes
- (b) Unstable on standing
- (c) Can be filtered
- (d) Homogeneous
Answer: (d) Homogeneous
Explanation: Suspensions are heterogeneous mixtures.
Explanation: Suspensions are heterogeneous mixtures.
Q.20
Which of the following is an emulsion?
- (a) Milk
- (b) Soil
- (c) Salt solution
- (d) Air
Answer: (a) Milk
Explanation: Milk is fat in water, a liquid–liquid colloid.
Explanation: Milk is fat in water, a liquid–liquid colloid.