Disposal of addition polymers
3 marks · NormalA city produces 950,000 tonnes of plastic waste each year. 70% of this is made up of addition polymers. Only 12% of the addition polymer waste is recycled, while the rest is sent to landfill.
Calculate the mass of addition polymer that is sent to landfill each year. Show your working.
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585,600 tonnes (±100)
Also accept: 585600
Common mistakes: Calculating percentage of total plastic waste rather than addition polymer waste.; Incorrect subtraction of recycled amount.
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Marking points
M1 · 1 mark · Finds the mass of addition polymer waste: 950,000 × 0.7 = 665,000 tonnes. (follow-through)
M2 · 1 mark · Calculates mass recycled: 12% of addition polymer waste = 665,000 × 0.12 = 79,800 tonnes (or equivalent method). (follow-through)
A1 · 1 mark · Subtracts recycled from total addition polymer to get mass sent to landfill: 665,000 – 79,800 = 585,200 tonnes (allow rounding to 585,600 tonnes for 3 significant figures). (follow-through)
Worked solution
Total plastic waste = 950,000 tonnes.
Addition polymer waste = 950,000 × 0.70 = 665,000 tonnes.
Mass recycled = 665,000 × 0.12 = 79,800 tonnes.
Mass sent to landfill = 665,000 – 79,800 = 585,200 tonnes.
(If using 3 significant figures, 585,600 tonnes is acceptable.)