Cambridge Secondary (7-9). Stage 9. Science. Learner's Book - Unit 8: Rates of reaction - Question 70

Investigate marble chips reacting with dilute hydrochloric acid. Measure the time taken to collect 25 cm³ of carbon dioxide in an inverted measuring cylinder over water. When your teacher has approved your plan, carry out the investigation and follow your safety precautions. Prepare 50 cm³ of each solution by diluting the acid provided as shown. Set up the apparatus, weigh the marble chips and place them in the flask. Add the acid and time how long it takes to collect 25 cm³ of CO₂. Record the acid used and the time; repeat with different concentrations.

| Solution | Acid / cm³ | Water / cm³ |
|---|---:|---:|
| A | 10 | 40 |
| B | 20 | 30 |
| C | 30 | 20 |
| D | 40 | 10 |
| E | 50 | 0 |