A school is choosing between two materials for making identical laboratory worktops. A life cycle assessment gives the following results for one worktop.
| Quantity | Material X | Material Y |
|---|---|---|
| Energy used in MJ | 520 | 410 |
| Water used in litres | 95 | 130 |
| Waste produced in kg | 8.4 | 6.1 |
| Effect on the landscape, rated by a panel from 1 to 5 | 2 | 4 |
| Harm caused by pollutants, rated by a panel from 1 to 5 | 3 | 2 |
For each panel rating, a higher value represents a greater environmental impact.
Which conclusion is supported by the data and is based only on quantities that can be given fairly reliable numerical values?
Material X uses less water and has less effect on the landscape.
Material X uses less water and produces less waste.
Material Y uses less energy and produces less waste.
Material Y uses less energy and causes less harm from pollutants.
99 exam-style questions on AQA GCSE Chemistry 10.2 Life cycle assessment and recycling, covering 10.2.1 Life cycle assessment and 10.2.2 Ways of reducing the use of resources. Each one has a worked solution and a mark scheme showing where the marks go.