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Primary General Studies, People and the Environment, Paper 2: air, climate and water
Primary General Studies, People and the Environment, Paper 2: air, climate and water
Ten items on PM2.5, greenhouse gases, food waste, usable fresh water, household water use, noise levels, trees and kWh, glass recycling and climate responsibility.
Focus PM2.5 reaches deep into the lungs; carbon dioxide is the main greenhouse gas; keep food waste separate; under 1% of water is usable fresh water; about 130 L per person a day; above 85 dB damages hearing; 1 kWh is one unit.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 25 |
| Difficulty mix | Foundation 4 · Intermediate 3 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: Primary General Studies: People and the Environment |
| Level | P4 to P6 |
02 Questions (10 items)
- FoundationWhat is PM2.5?
- FoundationWhich gas is the main greenhouse gas?
- FoundationHow should food waste at home be handled?
- FoundationIs much of the water on Earth fresh water that we can use?
- IntermediateA family of four uses 130 L per person each day. What is the daily total?
- IntermediateAbove what noise level can long exposure damage hearing?
- IntermediateA tree absorbs about 20 kg of carbon dioxide a year. How much do 10 trees absorb?
- ChallengeA 1200 W air conditioner runs for 8 hours. How many units of electricity is that?
- ChallengeCan glass bottles be recycled, and what do they become?
- Error redoError fix: polar bears are hit by climate change but it has nothing to do with Hong Kong. What is correct?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | Fine particles smaller than 2.5 micrometres that can reach deep into the lungs. | Traffic fumes and burning are the main sources, so cut outdoor exercise when air is bad. |
| 2 | Carbon dioxide. | Burning coal, oil and gas releases carbon dioxide, which warms the planet. |
| 3 | Keep it separate for recycling or composting instead of mixing it with other rubbish. | Food waste is wet, so mixing it in brings smells and dirty leachate. |
| 4 | Very little, under 1% of all the water on Earth. | Most water is sea water or locked in ice, so saving water matters. |
| 5 | 130 × 4 = 520 L. | Toilets, showers and laundry use the most, and a low-flow shower head cuts demand. |
| 6 | About 85 dB and above. | Building sites and headphones at full volume pass 85 dB, so shorten the exposure. |
| 7 | 20 × 10 = 200 kg. | Planting helps absorb carbon, yet cutting emissions works faster than offsetting. |
| 8 | 1200 × 8 ÷ 1000 = 9.6 kWh. | One unit is one kWh, and setting 25.5 °C with a fan saves power. |
| 9 | Yes, once rinsed they become new bottles or building material. | Glass can be recycled endlessly, but colours must be sorted to keep them clean. |
| 10 | Emissions everywhere drive warming, and power use and consumption in Hong Kong count too. | Melting ice and extreme weather affect food, sea levels and prices, so places are linked. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
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Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.
