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Following Carbon While the Gas Count Falls 4 questions
Following Carbon While the Gas Count Falls
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A classroom air model has a rigid chamber containing carbon monoxide, oxygen, and carbon dioxide. The model holds temperature fixed and counts gas molecules before and after a reaction. Only the reaction shown occurs, and no material enters or leaves.
2CO + O2 → 2CO2
| Record | CO molecules | O2 molecules | CO2 molecules |
|---|---|---|---|
| Before | 12 | 10 | 8 |
| After | 4 | Hidden | 16 |
Question 1
How many CO molecules reacted?
- 4
- 8
- 12
- 16
Question 2
Calculate the missing final O₂ count. Show how the equation connects the two reactants.
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Question 3
Use the two carbon-containing gases to show that the number of carbon atoms is the same before and after.
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The model pressure starts at 100 kPa. At fixed temperature and volume it is proportional to the total number of gas molecules.
Question 4
Predict the final pressure to the nearest whole kilopascal. Explain how the pressure can change even though the number of carbon atoms stays fixed.
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