Primary 5 Science Materials Quiz

Primary 5 Science Quiz - Materials: Answer Key

Total Marks: 40

Section A: Multiple Choice

Section B: Fill in the Blanks and Short Answer

9. [2 marks — ½ mark each]

Teaching note: Conductors allow electricity/heat to pass through easily. Most metals are conductors. Insulators block or resist the flow. Rubber and wood are non-metals and insulators. Copper and silver are metals and conductors.

10. [2 marks — 1 mark each acceptable reason]

Any two from:

• Steel is stronger / can support more weight than wood
• Steel is more durable / lasts longer without rotting
• Steel does not rot or decay when exposed to weather
• Steel is more rigid and maintains shape under heavy loads

Marking note: Accept valid property comparisons. "Steel is stronger" alone is sufficient for 1 mark. Must specify why the property matters for bridges (load-bearing, weather exposure).

11. [2 marks]

Paper absorbs water and becomes soft/weak when wet [1]. It would dissolve or break apart / lose its strength [1], so water would leak through the pipe.

Common mistake: Do not accept "paper is too thin" — must explain interaction with water.

12. [2 marks — 1 mark each]

(a) Iron nail (or aluminium frying pan if referring to iron content, but aluminium is NOT magnetic) — Iron nail is the correct answer [1]

Correction note: The aluminium frying pan is NOT magnetic. Only the iron nail is magnetic.

(b) Rubber gloves or wooden chopping board or glass cup [1]

Teaching note: Rubber is an excellent electrical insulator — this is why electricians wear rubber gloves. Wood and glass are also insulators.

13. [2 marks]

Translucent [1]. A translucent material lets some light through but scatters it, so you can see that the lamp is on but cannot see clear details of the bulb inside [1]. Transparent would be too bright/glaring; opaque would block all light.

14. [2 marks]

(a) Rigid [1] — it breaks rather than bends

(b) Less dense than water [1]. Objects that float are less dense than the liquid they float in.

Teaching note: Density determines floating/sinking. Floating = less dense; Sinking = more dense. Flexibility/rigidity is about how a material responds to force, separate from density.

Section C: Application and Reasoning

15. [4 marks]

(a) Metal conducts heat very well [1]. Heat from the food would pass quickly through the metal walls to the outside air, so the food would lose heat rapidly and get cold [1].

(b) Plastic [1]. Plastic is waterproof (won't leak), rigid (keeps shape), safe for food, and importantly it does NOT conduct heat [1], so heat stays inside the food longer.

Alternative acceptable: Glass — must explain that while glass conducts heat, a tight lid reduces convection, or that glass with plastic coating could work. Plastic is the strongest answer.

16. [4 marks]

(a) Wool [1] — 12 minutes (longest bar)

(b) Wool is a good insulator / poor conductor of heat [1]. It trapped the cold air inside and reduced heat gain from the warmer surroundings, slowing down melting [1].

(c) Aluminium foil [1]. It took only 3 minutes — the shortest time. Aluminium foil is a good conductor of heat, so it allowed heat from the surroundings to reach the ice quickly [1 for explanation if asked, but question asks to "explain" so both points needed].

Marking note: For (c), must name material AND explain — 1 mark total as stated, split as ½ + ½ if needed, but mark scheme says 1 mark. Accept: Aluminium foil; it is a good conductor so heat transfers quickly to the ice.

17. [4 marks]

(a) If the roof is not waterproof, rain would leak through [1], damaging the interior and making the house uncomfortable/unsafe.

Marking note: Accept any reasonable materials with valid properties. Must match property to function. Wood for door frame must mention it is strong/rigid; glass for window must include transparency.

18. [4 marks]

(a) [2 marks — ½ mark each]

Teaching clarification: A wooden pencil has a graphite (carbon) core that conducts, but the wood does not. For P5, expect "No" or accept discussion. In standard testing, metal key = Yes, Iron nail = Yes (1 mark for both correct). Plastic spoon = No, Rubber band = No (1 mark for both correct).

(b) The iron nail is a metal [1]. Metals contain free electrons that can move and carry electric current. The plastic spoon is made of plastic, which is an insulator — its electrons are tightly held and cannot move freely to carry current [1].

19. [4 marks]

(a) [2 marks — material suggestions must be sensible]

(b) [2 marks — 1 mark each for any two valid property explanations]

• Frame — light/rigid: Must be light so the kite can lift off, and rigid to hold shape against wind
• Sail — waterproof/light: Must be waterproof so rain doesn't soak and weigh it down; light so kite can fly
• String — strong/light: Must be strong to withstand pulling force; light to not drag kite down

Marking note: Accept reasonable materials with well-matched properties. At least two parts need property explanations for full marks.

20. [4 marks]

(a) Material Z [1]. Copper wire is a metal, so it should conduct electricity (conductor) [½] and be a flexible metal that can bend [½]. Material Z: sinks (dense metal), not magnetic (copper is non-magnetic), flexible (wire bends), conductor (metal property) [1 for reasoning].

(b) Material Y [1]. Wood floats (less dense than water) [½], is not magnetic, rigid (holds shape as a block) [½], and is an insulator [½]. Together these match wooden block properties [½]. Material W is also possible but is flexible — wood is typically rigid. Material Y is the best match.

Teaching note: Real woods vary — some float, some sink slightly. For P5, "wood floats" is standard teaching. The rigid/flexible distinction helps separate Y from W.

Marking Summary