Two solutions react and produce a gas. A student mixes the same volumes and concentrations of the solutions at different temperatures. The student measures the time taken to collect 40 cm3 of gas.
| Temperature (∘C^\circ\text{C}∘C) | 15 | 25 | 35 |
|---|---|---|---|
| Time to collect 40 cm3 of gas (s) | 196 | 101 | 48 |
Calculate how many times greater the mean rate is at 35 ∘C35\,^\circ\text{C}35∘C than at 15 ∘C15\,^\circ\text{C}15∘C.
Use the pattern in the results to suggest the time taken to collect 40 cm3 of gas at 45 ∘C45\,^\circ\text{C}45∘C.
122 exam-style questions on OCR GCSE Chemistry 5.2 Controlling reactions, covering 5.2.1 Measuring and interpreting rate of reaction, 5.2.2 Factors affecting rate and collision theory, and 5.2.3 Catalysts, activation energy and enzymes. Each one has a worked solution and a mark scheme showing where the marks go.