Question

Students were asked to set up an experiment. Each group was given 4 flasks, and each flask was set up according the table above. The flasks were sealed.



PART A If the flasks were left sealed for a week, flask number 1.____ would most likely have the largest amount of CO2?

PART B 2.____ would help reduce the amount of carbon dioxide produced from your answer to Part A.

1:
a. 1
b. 2
c. 3
d. 4

2:
a. Add a plant to the flask
b. Add a goldfish to the flask
c. Remove a plant from the flask
d. Do nothing as the carbon dioxide will naturally became diluted

Answer 1

To answer the questions, we will analyze the potential factors affecting carbon dioxide (CO2) levels in each flask based on common experimental setups.

### PART A
In experiments involving sealed flasks containing living organisms, it's common to predict which setup will produce the most CO2. Here’s a typical reasoning based on the options:

- **Flask 1** might contain only a plant performing photosynthesis (which absorbs CO2).
- **Flask 2** might contain a mixture of a plant and animal (which performs respiration, producing CO2).
- **Flask 3** might have more animals or no plants at all, leading to CO2 production from respiration only.
- **Flask 4** might contain just one plant or a different setup with less metabolic activity.

Given that animals respire and produce CO2, **flask number 2** (if it contains both a plant and an animal) would most likely have the largest amount of CO2 due to the respiratory process that occurs in animals combined with potential accumulation over a week.

8. **Answer for PART A**:
**2.** would most likely have the largest amount of CO2.

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### PART B
To reduce the amount of CO2 produced in the scenario above, we can consider the role of plants. Plants absorb CO2 during photosynthesis.

So, adding a plant would help to absorb CO2 from the atmosphere.

**Answer for PART B**:
**a. Add a plant to the flask** would help reduce the amount of carbon dioxide produced from your answer to Part A.

### Final Answers:
1. **2**
2. **a. Add a plant to the flask**