Question 2
22nd International Mathematics and Science Olympiad (IMSO)
Group and Individual Experiment Test · Kedah, Malaysia · 07 October 2025
Instructions:
1\. Do not turnover this page until you are told to do so.
2\. Write your ID Number and Seat Number on each space provided in the answer sheet.
3\. Write your answer only on the separate answer sheet. There are 6 pages in the answer sheet.
4\. Follow all the instructions carefully.
5\. There are two experiments in this test. Make sure to answer BOTH papers to get full points.
6\. For the group experiment: ONLY the procedure of the experiment is done by group. The paper must be answered individually.
7\. Complete all the sections in English. There are Section I, II and III for the Group Experiment and Section I, II, and III for the individual experiment.
8\. The marks awarded for each section or question is shown in brackets, [ ].
9\. There are 6 printed pages in this booklet, excluding this cover page.
10\. You have 120 minutes to complete this test.
Editorial scoring note: The source does not print a total score. Only three group data tables show [1 mark] each. This study package assigns 20 editorial points to each experiment (40 editorial points overall); these are not official totals. Printed marks are retained below. Both experiments share the printed 120 minutes; the individual activity additionally has a printed 45-minute limit. No candidate information or measured results is supplied.
GROUP EXPERIMENT · How Enzymes Make Reactions Faster
Objective
This experiment aims to test how different amounts of yeast affect the speed of balloon inflation when hydrogen peroxide breaks down and to connect this reaction to real-life applications.
Materials
A. A cup of 360mL of 3% hydrogen peroxide
B. A packet of active dry yeast
C. Warm water
D. Three identical clear plastic bottles
E. Three balloons
F. 10 mL graduated cylinder
G. ruler (in cm), stopwatch, marker, small cups
Procedure
By Group:
Note 1: The warm water will be distributed to your group by the invigilators.
1\. Using the bottles you used in the first experiment, label the bottles as A, B, and C. Then, pour 120 mL of hydrogen peroxide into each bottle.
2\. Label the small cups as A, B, and C. In the three small cups, prepare the yeast mixtures. Stir each cup 5–10 seconds.
| Cup | Content of the cup |
| --- | --- |
| A | 10 mL warm water |
| B | ¼ tsp yeast + 10 mL warm water |
| C | 1 tsp yeast + 10 mL warm water |
3\. Quickly pour the content of cup A into bottle A, immediately stretch the balloon over the mouth of the bottle and start the stopwatch. Record height at 0, 1, 2, 3, 4, 5, 6 min. Record everything on the data sheet.
Note 2: Measure balloon height from the bottle mouth to the highest point of the balloon (cm).
4\. Repeat for Cup B and C.
Individually:
5\. Draw a line graph of your result.
6\. Compute for the initial rate for each condition using the first two minutes.
Initial rate = (height at 2 min − height at 0 min) ÷ 2
Section I. Data Table
Table 1. ________________________________________
| Time (min) | Bottle A (cm) | Bottle B (cm) | Bottle C (cm) |
| --- | --- | --- | --- |
| 0 | | | |
| 1 | | | |
| 2 | | | |
| 3 | | | |
| 4 | | | |
| 5 | | | |
| 6 | | | |
[1 mark]
Table 2. ________________________________________
| Time (min) | Observation after 5 minutes |
| --- | --- |
| A | |
| B | |
| C | |
[1 mark]
Table 3. ________________________________________
| Time (min) | Height at 2 min | Height at 0 min | Initial Rate |
| --- | --- | --- | --- |
| A | | | |
| B | | | |
| C | | | |
[1 mark]
Section II. Graph
Graph your results on the answer sheet.
Section III. Guide Questions
1\. Which bottle acted as the control?
2\. Using the initial rate, which balloon inflated fastest?
3\. Which reached the highest final height at 6 min?
4\. By what percent did the fastest initial rate exceed the Control? Assume that the initial rate of the control is 0.7.
5\. Based on this experiment and your knowledge of biological catalysts, provide a detailed scientific explanation for your observations during the experiment.
6\. Identify two (2) possible sources of error for this experiment.
7\. Why do our bodies need the enzyme catalase, and what might happen if we did not have it?
8\. When doctors use hydrogen peroxide to clean small wounds, why do bubbles appear?
9\. Yeast is also used in bread-making. How is the gas released in bread different from the gas produced in this experiment?
--- END OF EXPERIMENT TEST ---
Group and Individual Experiment Test · Kedah, Malaysia · 07 October 2025
Instructions:
1\. Do not turnover this page until you are told to do so.
2\. Write your ID Number and Seat Number on each space provided in the answer sheet.
3\. Write your answer only on the separate answer sheet. There are 6 pages in the answer sheet.
4\. Follow all the instructions carefully.
5\. There are two experiments in this test. Make sure to answer BOTH papers to get full points.
6\. For the group experiment: ONLY the procedure of the experiment is done by group. The paper must be answered individually.
7\. Complete all the sections in English. There are Section I, II and III for the Group Experiment and Section I, II, and III for the individual experiment.
8\. The marks awarded for each section or question is shown in brackets, [ ].
9\. There are 6 printed pages in this booklet, excluding this cover page.
10\. You have 120 minutes to complete this test.
Editorial scoring note: The source does not print a total score. Only three group data tables show [1 mark] each. This study package assigns 20 editorial points to each experiment (40 editorial points overall); these are not official totals. Printed marks are retained below. Both experiments share the printed 120 minutes; the individual activity additionally has a printed 45-minute limit. No candidate information or measured results is supplied.
GROUP EXPERIMENT · How Enzymes Make Reactions Faster
Objective
This experiment aims to test how different amounts of yeast affect the speed of balloon inflation when hydrogen peroxide breaks down and to connect this reaction to real-life applications.
Materials
A. A cup of 360mL of 3% hydrogen peroxide
B. A packet of active dry yeast
C. Warm water
D. Three identical clear plastic bottles
E. Three balloons
F. 10 mL graduated cylinder
G. ruler (in cm), stopwatch, marker, small cups
Procedure
By Group:
Note 1: The warm water will be distributed to your group by the invigilators.
1\. Using the bottles you used in the first experiment, label the bottles as A, B, and C. Then, pour 120 mL of hydrogen peroxide into each bottle.
2\. Label the small cups as A, B, and C. In the three small cups, prepare the yeast mixtures. Stir each cup 5–10 seconds.
| Cup | Content of the cup |
| --- | --- |
| A | 10 mL warm water |
| B | ¼ tsp yeast + 10 mL warm water |
| C | 1 tsp yeast + 10 mL warm water |
3\. Quickly pour the content of cup A into bottle A, immediately stretch the balloon over the mouth of the bottle and start the stopwatch. Record height at 0, 1, 2, 3, 4, 5, 6 min. Record everything on the data sheet.
Note 2: Measure balloon height from the bottle mouth to the highest point of the balloon (cm).
4\. Repeat for Cup B and C.
Individually:
5\. Draw a line graph of your result.
6\. Compute for the initial rate for each condition using the first two minutes.
Initial rate = (height at 2 min − height at 0 min) ÷ 2
Section I. Data Table
Table 1. ________________________________________
| Time (min) | Bottle A (cm) | Bottle B (cm) | Bottle C (cm) |
| --- | --- | --- | --- |
| 0 | | | |
| 1 | | | |
| 2 | | | |
| 3 | | | |
| 4 | | | |
| 5 | | | |
| 6 | | | |
[1 mark]
Table 2. ________________________________________
| Time (min) | Observation after 5 minutes |
| --- | --- |
| A | |
| B | |
| C | |
[1 mark]
Table 3. ________________________________________
| Time (min) | Height at 2 min | Height at 0 min | Initial Rate |
| --- | --- | --- | --- |
| A | | | |
| B | | | |
| C | | | |
[1 mark]
Section II. Graph
Graph your results on the answer sheet.
Section III. Guide Questions
1\. Which bottle acted as the control?
2\. Using the initial rate, which balloon inflated fastest?
3\. Which reached the highest final height at 6 min?
4\. By what percent did the fastest initial rate exceed the Control? Assume that the initial rate of the control is 0.7.
5\. Based on this experiment and your knowledge of biological catalysts, provide a detailed scientific explanation for your observations during the experiment.
6\. Identify two (2) possible sources of error for this experiment.
7\. Why do our bodies need the enzyme catalase, and what might happen if we did not have it?
8\. When doctors use hydrogen peroxide to clean small wounds, why do bubbles appear?
9\. Yeast is also used in bread-making. How is the gas released in bread different from the gas produced in this experiment?
--- END OF EXPERIMENT TEST ---