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Is Matter Around Us Pure? — Class 9 CBSE Science MCQs with Solutions
Free Class 9 CBSE Science Is Matter Around Us Pure? MCQs with step-by-step solutions. Practise online on Prepizo — no login needed.
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Sample questions with solutions
Q1 — easy
A homogeneous mixture of two or more substances is called a:
A. Suspension
B. Solution (True solution) ✓ Correct
C. Colloid
D. Compound
Solution: A true solution is a uniform, homogeneous mixture.
Q2 — easy
Scattering of a beam of light as it passes through a colloidal solution is known as:
A. Reflection
B. Tyndall Effect ✓ Correct
C. Refraction
D. Dispersion
Solution: Tyndall effect is light scattering by colloidal particles.
Q3 — easy
Tincture of Iodine is a solution where Iodine acts as solute and solvent is:
A. Water
B. Alcohol ✓ Correct
C. Acetone
D. Ether
Solution: Tincture of Iodine = Iodine (solute) dissolved in Alcohol (solvent).
Q4 — easy
Milk and Fog are classic real-world examples of:
A. True solutions
B. Colloidal solutions ✓ Correct
C. Suspensions
D. Pure compounds
Solution: Milk (emulsion) and fog (aerosol) are colloidal systems.
Q5 — easy
A heterogeneous mixture whose particles settle down upon standing undisturbed (e.g. chalk in water) is a:
A. Solution
B. Suspension ✓ Correct
C. Colloid
D. Alloy
Solution: Suspensions contain visible, unstable particles that settle out.
Q6 — easy
Pure chemical substance consisting of only ONE type of atom is an:
A. Element ✓ Correct
B. Compound
C. Mixture
D. Alloy
Solution: An element cannot be broken down into simpler substances chemically.
Q7 — easy
Which of the following is a non-metallic liquid element at room temperature?
A. Mercury
B. Bromine ✓ Correct
C. Iodine
D. Chlorine
Solution: Bromine is a non-metallic liquid element at room temp (Mercury is metallic liquid).
Q8 — easy
Air is a mixture because its components can be separated by physical methods and:
A. It has a fixed formula
B. It shows properties of constituent gases ✓ Correct
C. It boils at fixed temperature
D. It forms chemical bonds
Solution: Air retains properties of its individual constituent gases (N₂, O₂, CO₂).
Q9 — easy
Brass is a solid-solid homogeneous mixture (alloy) consisting of:
A. Copper and Tin
B. Copper and Zinc ✓ Correct
C. Iron and Carbon
D. Lead and Tin
Solution: Brass is an alloy of ~70% Copper and ~30% Zinc.
Q10 — easy
Solubility of a solid solute in a liquid solvent generally _______ with increase in temperature.
A. Decreases
B. Increases ✓ Correct
C. Remains constant
D. Drops to zero
Solution: Heating generally increases thermal dissolution rate and solubility of solids.
Q11 — easy
Maximum amount of solute that can dissolve in 100 g of solvent at a specific temperature is its:
A. Concentration
B. Solubility ✓ Correct
C. Molarity
D. Saturation point
Solution: Solubility measures saturation concentration at a given temperature.
Q12 — easy
When no more solute can be dissolved in a solution at a given temperature, it is called a:
A. Unsaturated solution
B. Saturated solution ✓ Correct
C. Super-dilute solution
D. Concentrated solution
Solution: A saturated solution holds maximum possible solute at that temperature.
Q13 — easy
Cream is separated from milk commercially by the process of:
A. Filtration
B. Centrifugation ✓ Correct
C. Evaporation
D. Sublimation
Solution: Centrifugation uses rapid spinning to separate dense and light phases.
Q14 — easy
Dye components in black ink are separated using:
A. Distillation
B. Chromatography ✓ Correct
C. Crystallization
D. Filtration
Solution: Paper chromatography separates dissolved pigments based on solubility rates.
Q15 — easy
Which of the following is a chemical change?
A. Cutting a tree
B. Rusting of iron ✓ Correct
C. Melting of butter
D. Dissolving salt in water
Solution: Rusting forms a new substance (hydrated iron oxide).