A chemist investigated whether a solid, W, acts as a catalyst in a reaction that produces a gas. The reaction was carried out twice. All conditions other than the presence of W were kept the same. After the second experiment, W was separated, dried and reweighed.
| Measurement | Without W | With W |
|---|---|---|
| Initial rate of gas production in cm3/s\text{cm}^3\text{/s}cm3/s | 0.35 | 1.40 |
| Mass of W added in g\text{g}g | — | 0.80 |
| Mass of W recovered in g\text{g}g | — | 0.80 |
Explain whether W acts as a catalyst. Use the data and collision theory in your answer.
127 exam-style questions on AQA GCSE Chemistry 6.1 Rate of reaction, covering 6.1.1a Calculating rates of reactions, 6.1.1b Gradient of a tangent as rate, 6.1.2 Factors which affect the rates of chemical reactions, 6.1.3 Collision theory and activation energy, and 6.1.4 Catalysts. Each one has a worked solution and a mark scheme showing where the marks go.