Overhead power cables hang between pylons. They must be light, cheap and good conductors of electricity.
| Metal | Relative electrical conductivity | Density / g cm−3\mathrm{g\,cm^{-3}}gcm−3 | Relative cost |
|---|---|---|---|
| aluminium | 37 | 2.7 | 1 |
| copper | 60 | 8.9 | 4 |
| silver | 63 | 10.5 | 300 |
| steel | 6 | 7.9 | 0.3 |
Statement 1: silver is not used for the cables mainly because of its high cost
Statement 2: a copper cable would be lighter than an aluminium cable of the same size
Statement 3: aluminium is used because it conducts well enough, has a low density and is cheap
Which statements are correct?
1 only
1 and 3 only
2 and 3 only
1, 2 and 3
42 exam-style questions on Edexcel GCSE Chemistry 6.1 Transition metals, alloys and corrosion, covering 6.1.1 Properties of transition metals, 6.1.2 Corrosion and its prevention, and 6.1.3 Alloys and the uses of metals. Each one has a worked solution and a mark scheme showing where the marks go.