A gas-phase process takes place in a cylinder fitted with a movable piston. In each test, the same numbers of particles of gases R and S are used and the temperature is kept at 25 °C. The time taken to form a fixed amount of product is measured.
| Initial pressure in kPa | Time taken in s |
|---|---|
| 80 | 150 |
| 120 | 100 |
| 160 | 75 |
Calculate the time expected at an initial pressure of 200 kPa if the pattern in the results continues.
Explain the pattern in the results using the reacting particle model. Include the effects on collision frequency and collision energy in your answer.
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.