The problems are on the properties of materials worksheet. Try them on your own first, then compare with the answers below.
Quick answer: Materials have properties such as hardness, electrical conductivity, magnetism and flexibility. These worked answers correct the 20 problems of the grade 6 science worksheet on properties of materials, from what is a property? to mystery rod: each solution shows the formula, the substitution and the final answer with its unit.
Check each answer after you finish all the problems. Look at the method as well as the result, because the reasoning about properties earns the marks in a test.
Level: Grade 6 science (Year 7 · Class 6) · Curriculum: MS-PS1-3
Problem 1 What is a property?
1. A property is a feature of a material that we can observe or measure.2. Any two of: hard, shiny, conducts electricity, conducts heat, magnetic. Example: hard and magnetic.
Problem 2 Conductor or insulator?
1. Conductors: copper wire, iron nail, graphite pencil lead. Insulators: rubber glove, dry wood, plastic ruler.2. The bulb: it lights if the material conducts.
Problem 3 Magnet sort
1. The steel paper clip and the iron nail are attracted.2. No, aluminium is not magnetic.
Problem 4 Scratch order
Q is scratched by both, so Q is softest. P scratches R, so R is softer than P. Q, then R, then P.Problem 5 Match the property
(a) Electrical conductivity. (b) Flexibility. (c) Hardness.Problem 6 Reading a results table
1. K (conducts, magnetic, hard).2. L (insulator, not magnetic, soft).
Problem 7 Saucepan design
1. Metal conducts heat well, so the heat reaches the food quickly.2. Plastic conducts heat poorly, so the handle stays cool enough to hold. Metal base, insulating handle.
Problem 8 Cans at Kofi’s school
1. 120 − 45 = 75 aluminium cans.2. 45 ÷ 120 × 100 = 37.5 % steel.
Problem 9 Bending rods
1. The plastic rod sags most, so it is the most flexible.2. 12 mm ÷ 1 mm = 12 times.
Problem 10 Electric cable
1. Copper is a good conductor, so the current flows along the core.2. Plastic is an insulator and flexible, so it stops shocks and lets the cable bend. Core conducts, covering insulates.
Problem 11 Fair test: flexibility
1. Keep the same: strip length, strip width and thickness, the hanging mass, how far the strip overhangs the bench (any two).2. Measure: the sag of the free end in millimetres.
Problem 12 Aluminium savings
Recycling per kg: 200 × 0.05 = 10 MJ. For 20 kg: 10 × 20 = 200 MJ.New: 200 × 20 = 4000 MJ. Saved: 4000 − 200 = 3800 MJ.
Problem 13 Stirring soup
Copper conducts heat to the hand. The plastic spoon would soften at 70 °C, below the soup temperature of about 100 °C. Wood is a poor conductor and does not soften. The wooden spoon is the best choice.Problem 14 Could it be aluminium?
Aluminium is not magnetic, so this metal cannot be aluminium. It could be iron or steel, which conduct and are attracted by magnets.Problem 15 Wrong conclusion
Diego generalised from one example. Testing a copper wire or an aluminium strip with the magnet shows they are not attracted. Not all metals are magnetic; only iron, steel, nickel and cobalt are.Problem 16 Scrap yard sort
Steel: 0.40 × 36 = 14.4 kg. Remaining: 36 − 14.4 = 21.6 kg. Aluminium: 0.60 × 21.6 = 12.96 kg. Glass: 21.6 − 12.96 = 8.64 kg. Steel 14.4 kg, aluminium 12.96 kg, glass 8.64 kg.Problem 17 Two samples in series
The current must pass through both samples. Copper and wood: wood blocks the current, so the bulb stays off. Copper and graphite: both conduct, so the bulb lights.Problem 18 Decision matrix
A: 12 + 6 + 5 = 23. B: 15 + 8 + 2 = 25. C: 9 + 4 + 5 = 18. D: 3 + 10 + 4 = 17. B (ceramic) has the highest score, 25.Problem 19 Bottle bank
1. Daily: 500 × 0.30 = 150 kg. Year: 150 × 365 = 54 750 kg = 54.75 t. 54 750 kg = 54.75 tonnes.2. Glass can be melted and reshaped many times without losing its properties, so the same material is used again.
