A manufacturer is choosing a steel for the cutting jaws of a hand tool. The jaws must remain sharp for at least 800 cuts and must absorb at least 15 J of energy in an impact test before they fracture.
Samples of each steel have the same dimensions and are tested under the same conditions.
| Steel | Carbon content (%) | Number of cuts before the jaws become blunt | Energy absorbed before fracture (J) |
|---|---|---|---|
| A | 0.20 | 260 | 34 |
| B | 0.80 | 980 | 18 |
| C | 1.30 | 1350 | 9 |
Suggest which steel the manufacturer should use. Use the data to justify your answer.
Explain why steel B remains sharp for longer than steel A. Use the arrangement of atoms 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.