A council needs one route-marker post at each location in a country park. The council compares the resources used by timber and aluminium posts over 20 years.
| Material | Source of raw material | Number of posts needed during 20 years | Total manufacturing energy during 20 years in MJ | Percentage recovered for recycling (%) |
|---|---|---|---|---|
| Timber | Trees from a managed plantation, replanted after harvesting | 3 | 240 | 35 |
| Aluminium | Metal ore | 1 | 520 | 90 |
Calculate the percentage of aluminium posts that are not recovered for recycling. Use the table.
Evaluate whether timber or aluminium is the more sustainable material for the posts. Use the table and your own knowledge.
87 exam-style questions on AQA GCSE Chemistry 10.1 Using the Earth's resources and obtaining potable water, covering 10.1.1 Using the Earth's resources and sustainable development, 10.1.2 Potable water, 10.1.3 Waste water treatment, and 10.1.4 Alternative methods of extracting metals. Each one has a worked solution and a mark scheme showing where the marks go.