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Improving gas-volume measurement accuracy
A student investigated the relationship between temperature and the rate of photosynthesis. The student measured the volume of gas produced by an aquatic plant in 1 hour. The student collected the gas in a measuring cylinder. Table 2 shows the results.
| Temperature in °C | Volume of gas produced in 1 hour in cm³ |
|---|---|
| 10 | 1 |
| 15 | 2 |
| 20 | 4 |
| 25 | 8 |
| 30 | 16 |
| 35 | 16 |
| 40 | 2 |
| 45 | 0 |
How could the student increase the accuracy of the results? Tick one box.
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Marking points
- 1 Selects the option measuring gas volume to 0.5 cm³.
Why this answer loses marks
Repeat for longer so that more gas is collected.
A longer collection changes the procedure but not how finely the volume is read; accuracy improves through smaller measurement increments.