A student mixes two colourless solutions. As the reaction takes place, the mixture turns blue.
She keeps the volumes and concentrations of both solutions the same. She records the time taken for the mixture to reach the same shade of blue at two temperatures.
Relative rate is calculated using:
relative rate=1time\displaystyle \text{relative rate} = \frac{1}{\text{time}}relative rate=time1
| Temperature in ∘C^\circ\mathrm{C}∘C | Time in s\mathrm{s}s | Relative rate |
|---|---|---|
| 20 | 80 | 0.0125 |
| 30 | 40 | ______ |
Complete the missing entry in the relative rate column.
Write the unit for this column.
State which temperature gives the faster reaction.
State how increasing the temperature from 20 ∘C20\,^\circ\mathrm{C}20∘C to 30 ∘C30\,^\circ\mathrm{C}30∘C affects the average kinetic energy of the particles.
Explain, in terms of collisions, how this change in average kinetic energy affects the rate of reaction.
122 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.