An engineer tests three solids in a reaction that makes a product used in paints. Each test uses the same mass of reactants at the same temperature. The engineer measures the time taken to make 10 g of product and the mass of the solid before and after the reaction. The engineer also measures the time taken to make 10 g of product with no solid added.
| Solid added | Time taken to make 10 g of product in s | Mass of solid before reaction in g | Mass of solid after reaction in g |
|---|---|---|---|
| Solid A | 90 | 5.0 | 5.0 |
| Solid B | 220 | 5.0 | 4.6 |
| Solid C | 150 | 5.0 | 4.7 |
| No solid | 180 | – | – |
Which solid acted as a catalyst? Explain your answer and predict whether it could be used in another batch.
91 exam-style questions on AQA GCSE Chemistry 1.3 Properties of transition metals, covering 1.3.1 Comparison with Group 1 elements and 1.3.2 Typical properties of transition metals. Each one has a worked solution and a mark scheme showing where the marks go.