WA1 Practice Paper: Weighted Assessment 1 — mark scheme
Secondary 1 · Lower Secondary Science (G2 / G3)
Mark scheme
Weighted Assessment 1
WA1 Practice Paper · Maximum mark: 30
Notes for markers
- Award one mark for each point marked [1], up to the marks shown for the part.
- Accept answers worded differently that show the same understanding.
- Units are required where the answer line shows one. ecf: allow an error carried forward.
Section A: Multiple-choice questions[10 marks]
| Question | Answer | |
|---|---|---|
| 1 | AA thermometer measures the temperature and a stopwatch measures the time taken. | 1 |
| 2 | CVolume = 55.0 − 45.0 = 10.0 cm³. Density = mass ÷ volume = 27.0 ÷ 10.0 = 2.7 g/cm³. | 1 |
| 3 | BA flame over a circle means oxidising: the substance makes other materials burn more fiercely. | 1 |
| 4 | DThe yellow luminous flame is easy to see, so nobody touches the burner by accident. | 1 |
| 5 | AThe length is the variable the student changes on purpose. | 1 |
| 6 | DA wire must carry electricity and bend without breaking. | 1 |
| 7 | CA harder material scratches a softer one: P is harder than Q, and Q is harder than R. | 1 |
| 8 | AObjects that are less dense than water float in it. | 1 |
| 9 | BPoor conductors of heat (insulators) stop the handle from getting too hot to hold. | 1 |
| 10 | B25 °C is above the melting point but below the boiling point, so the substance is a liquid. | 1 |
Section B: Structured questions[20 marks]
| Question | Answer and marking points | Marks |
|---|---|---|
| 1(a) | A measuring cylinder (e.g. 25 cm³). [1] | 1 |
| 1(b) | Any two: point the mouth of the tube away from everyone; hold it with a test-tube holder; wear safety goggles; heat gently and keep the tube moving.
| 2 |
| 1(c) | The non-luminous flame is hotter, because the gas burns completely, so the water heats faster. It also does not leave soot on the boiling tube.
| 2 |
| Total for Question 1 | 5 | |
| 2(a) | 3.0 × 2.0 × 3.0 = 18 cm³ [1] | 1 |
| 2(b) | Density = mass ÷ volume = 54 ÷ 18 = 3.0 g/cm³
Allow error carried forward from (a). | 2 |
| 2(c) | It sinks, because its density (3.0 g/cm³) is greater than the density of water.
The explanation mark depends on the comparison of densities. | 2 |
| Total for Question 2 | 5 | |
| 3(a) | W — it conducts electricity and is flexible.
| 2 |
| 3(b) | X — it does not conduct electricity, so it insulates the wire, and it is flexible.
| 2 |
| 3(c) | Y — it has a very high melting point and conducts heat poorly. [1] The reason is not required for the mark. | 1 |
| Total for Question 3 | 5 | |
| 4(a) | Temperature of the water [1] Reject “heat” or “the water” alone. | 1 |
| 4(b) | Time taken for the sugar to dissolve [1] Accept “dissolving time”. Reject “the sugar” or “how much sugar dissolves”. | 1 |
| 4(c) | Any two: the volume of water; the mass of sugar (5 g); the type or grain size of sugar; the amount of stirring.
| 2 |
| 4(d) | To calculate an average, so the results are more reliable.
| 1 |
| Total for Question 4 | 5 |
— End of mark scheme —