A company is comparing two casings for a portable air-quality monitor. Both casings protect the monitor for the same working life.
Customers can return used casings through the company's collection scheme. The energy used to make recycled aluminium is 5% of the energy needed to make the same mass of new aluminium.
| Casing material | Mass of one casing (g) | Energy needed to make new material (MJ/kg) | Recycled material in each casing (%) | Used casings collected for recycling (%) |
|---|---|---|---|---|
| Aluminium | 72 | 180 | 70 | 88 |
| PET | 48 | 82 | 0 | 55 |
Calculate the energy needed to make the material for one casing of each type.
Give each answer in MJ.
Evaluate which casing is likely to have the lower environmental impact.
Use the data and your calculations in your answer.
136 exam-style questions on OCR GCSE Chemistry 6.1 Improving processes and products, covering 6.1.1 Extracting metals industrially and by electrolysis, 6.1.2 Life cycle assessment and recycling, 6.1.3 Biological methods of metal extraction, 6.1.4 The Haber process and the production of fertilisers, 6.1.5 Alloys and their uses, 6.1.6 Corrosion and its prevention, 6.1.7 Comparing and selecting materials, and 6.1.8 Industrial conditions, rate and position of equilibrium. Each one has a worked solution and a mark scheme showing where the marks go.