A company compares two reusable food containers. Each container is used for 200 washes per year for four years. The table shows some life-cycle assessment data.
| Stage | Container A | Container B |
|---|---|---|
| Energy used in manufacture (MJ) | 18 | 30 |
| Energy used per wash (MJ) | 0.10 | 0.04 |
| Crude oil used as a raw material (kg) | 0.25 | 0.60 |
Calculate the total energy used by each container over four years of use. Explain why these results alone do not show which container has the lower overall environmental impact.
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.