In experiment 1, magnesium ribbon reacts with hydrochloric acid. Experiment 2 is the same except for one or two changes. The acid is in excess in both experiments.
| Time in s | Volume of hydrogen in experiment 1 in cm3\mathrm{cm^{3}}cm3 | Volume of hydrogen in experiment 2 in cm3\mathrm{cm^{3}}cm3 |
|---|---|---|
| 0 | 0 | 0 |
| 10 | 30 | 34 |
| 20 | 52 | 40 |
| 30 | 68 | 40 |
| 40 | 78 | 40 |
| 50 | 80 | 40 |
| 60 | 80 | 40 |
Which changes to experiment 1 could give the results for experiment 2?
half the mass of magnesium ribbon, with acid of a higher concentration
the same mass of magnesium ribbon, with acid of a higher concentration
half the mass of magnesium ribbon, with acid of a lower concentration
the same mass of magnesium powder, with acid of the same concentration
127 exam-style questions on Edexcel GCSE Chemistry 8.1 Rates of reaction, covering 8.1.1 Measuring and interpreting rates of reaction, 8.1.2 Collision theory and the factors affecting rate, and 8.1.3 Catalysts and enzymes. Each one has a worked solution and a mark scheme showing where the marks go.