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

With a partner, list as many of the ways you can of telling that a reaction has taken place. Share your ideas with the class.

Can you suggest ways in which you could measure how quickly a reaction takes place? Share your ideas with the class.

Write the word and symbol equations for the reaction of magnesium with sulfuric acid.

This table shows results from magnesium reacting with dilute sulfuric acid in the gas-syringe apparatus. How can you tell from the table that the reaction has finished at 270 seconds?

| Time (s) | Total hydrogen volume (cm³) |
|---|---|
| 0 | 0 |
| 30 | 10 |
| 60 | 20 |
| 90 | 26 |
| 120 | 40 |
| 150 | 48 |
| 180 | 54 |
| 210 | 60 |
| 240 | 64 |
| 270 | 66 |
| 300 | 66 |
| 330 | 66 |

The gas syringe has a capacity of 100 cm³. Suggest what might happen if you used a lot more magnesium and acid, so that more than 100 cm³ of hydrogen gas was formed. What could be done to reduce the risk of an accident?

The graph shows the hydrogen results from the magnesium–sulfuric acid reaction. Which result is anomalous? Explain how you identified it, and say what you would expect the result to be.

Write the word equation for the reaction between copper carbonate and hydrochloric acid.

Use the graph of carbon dioxide volume from copper carbonate and hydrochloric acid to find the average rate of reaction between 60 and 80 seconds. How does this compare with the rate between 10 and 30 seconds (1 cm³/s)?

With a partner, discuss why you may need to plot a graph of your results when you carry out an investigation.

Discuss what makes a good graph: which variable goes on each axis, the scale, labels, how points are plotted, and how you decide to join them.

Make a poster, slide presentation or another presentation to illustrate how you produce the best possible graphs. Present it to another group or the whole class. You will need poster materials and/or access to computers.

Assess the presentations that other groups make to you.

Investigate calcium carbonate reacting with hydrochloric acid. You may measure mass of carbon dioxide lost using a balance, gas volume using a gas syringe, or gas collected over water. Answer questions 1–3 before starting. Assemble the equipment and place calcium carbonate in the flask. Add hydrochloric acid, start a timer and record the initial mass or volume. Measure every 30 seconds until three consecutive readings are the same.

Investigate calcium carbonate reacting with hydrochloric acid. You may measure mass of carbon dioxide lost using a balance, gas volume using a gas syringe, or gas collected over water. Make a list of the equipment you will need.

Investigate calcium carbonate reacting with hydrochloric acid. You may measure mass of carbon dioxide lost using a balance, gas volume using a gas syringe, or gas collected over water. Write a risk assessment for your investigation.

Investigate calcium carbonate reacting with hydrochloric acid. You may measure mass of carbon dioxide lost using a balance, gas volume using a gas syringe, or gas collected over water. Prepare a table for your results.

Investigate calcium carbonate reacting with hydrochloric acid. You may measure mass of carbon dioxide lost using a balance, gas volume using a gas syringe, or gas collected over water. Plot a graph of your results and describe how the rate of reaction changes over time.

Investigate calcium carbonate reacting with hydrochloric acid. You may measure mass of carbon dioxide lost using a balance, gas volume using a gas syringe, or gas collected over water. What problems did you have when you carried out this reaction? How might these have affected your results?

Investigate calcium carbonate reacting with hydrochloric acid. You may measure mass of carbon dioxide lost using a balance, gas volume using a gas syringe, or gas collected over water. How could you improve the reliability of your results?

Find the surface area of each different face of this book. Record the surface area for each face.