Earth's resources

9.What is one benefit of recycling?

10.What is plastic made from?

11.What does using resources sustainably mean?

12.Which of the following is an example of reusing rather than recycling?

13.A town uses 500 litres of water per person per day. If the population is 10,000, what is the total daily water usage in litres?

14.A recycling plant processes 200 kg of aluminium cans. It costs £0.50 per kg to recycle, while extracting new aluminium costs £1.20 per kg. How much money is saved by recycling this batch?

15.The graph shows the energy required to produce 1 kg of aluminium by extraction (E) and by recycling (R). If E = 200 MJ and R = 20 MJ, what percentage of energy is saved by recycling?

16.A student investigates how the number of times a plastic bottle is reused affects its mass. The results are shown in the table. What is the most likely reason for the decrease in mass after multiple uses?

17.A factory extracts iron ore from the ground. The ore contains 40% iron by mass. How many kilograms of ore are needed to obtain 100 kg of iron?

18.The table shows the energy used to produce 1 kg of different materials. Which material is most energy efficient to recycle?

19.A company reduces its plastic packaging by 20% per product. If they produce 10,000 products per year, how much plastic is saved annually if each product originally used 50 g of plastic?

20.A graph shows the amount of waste sent to landfill over 10 years. The line decreases from 1000 tonnes to 600 tonnes. What is the percentage decrease?

21.Which of the following is a renewable resource?

22.A student measures the mass of a sample of aluminium before and after recycling. The original mass is 50 g, and the recycled mass is 45 g. What is the percentage loss?

23.A pie chart shows the composition of household waste: 30% paper, 20% plastic, 25% food, 15% metal, 10% glass. If a household produces 200 kg of waste per year, what mass of plastic is thrown away?

24.A student investigates the energy required to recycle aluminium cans. They melt 100 g of used cans and measure the energy input as 250 kJ. The theoretical energy to melt pure aluminium is 397 kJ/kg. What is the percentage of the theoretical energy actually used?

25.In an experiment to compare the energy needed to extract copper from its ore versus recycling copper, a student heats 50 g of copper ore and measures the energy input as 800 kJ. The same mass of recycled copper requires 200 kJ. What is the ratio of energy for extraction to energy for recycling?

26.A student tests the pH of soil from a landfill site and a nearby garden. The landfill soil has pH 5.0, the garden soil pH 7.0. Which statement best explains the difference?

27.A student wants to compare the rate of decomposition of different types of waste. They bury samples of paper, plastic, and vegetable peel in soil and measure mass loss after 4 weeks. Which variable should be kept constant?

28.A factory extracts iron from iron ore (Fe₂O₃). The ore contains 70% iron(III) oxide by mass. How many tonnes of ore are needed to produce 100 tonnes of iron? (Ar: Fe = 56, O = 16)

29.Which of the following is a finite resource?

30.A student measures the volume of water used by a dripping tap over 1 hour. The volume collected is 150 mL. If the tap drips at a constant rate, how much water is wasted in a day?

31.A recycling company collects 500 kg of plastic bottles. After sorting and cleaning, 450 kg is suitable for recycling. The recycling process yields 400 kg of recycled plastic pellets. What is the overall percentage yield from collected bottles to recycled pellets?

32.Which of the following is an advantage of recycling aluminium compared to extracting it from bauxite ore?

33.What does it mean to reuse a resource?

34.A student investigates the effect of temperature on the rate of decomposition of vegetable waste. They set up three beakers with equal masses of vegetable waste at 10°C, 20°C, and 30°C. After 2 weeks, they measure the mass loss. Which beaker is likely to have the greatest mass loss?

35.A power station burns coal to generate electricity. The coal contains 80% carbon by mass. Burning 1 kg of carbon releases 32.8 MJ of energy. If the power station burns 1000 kg of coal per hour and is 40% efficient, what is the useful electrical energy output per hour?

36.A student investigates the energy required to recycle aluminium cans. They melt 100 g of used cans and measure the energy input as 250 kJ. The theoretical energy needed to melt 100 g of aluminium is 200 kJ. What is the percentage efficiency of the recycling process?

37.A factory extracts iron from iron ore (Fe₂O₃). The ore contains 70% iron(III) oxide by mass. How many tonnes of ore are needed to produce 100 tonnes of iron? (Ar: Fe=56, O=16)

38.The table shows the energy used to produce 1 kg of different materials. Which material is most energy efficient to recycle? Material | Energy to extract (MJ/kg) | Energy to recycle (MJ/kg) Aluminium | 200 | 20 Copper | 100 | 30 Steel | 50 | 25 Glass | 30 | 15

39.A student measures the mass of a sample of aluminium before and after recycling. The original mass is 50 g, and the recycled mass is 45 g. What is the percentage loss of mass during recycling?

40.A pie chart shows the composition of household waste: 30% paper, 20% plastic, 25% food, 15% metal, 10% glass. If a household produces 200 kg of waste per year, what mass of plastic waste is produced?