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Checking Mass When Water Vapor Replaces Air 4 questions
Checking Mass When Water Vapor Replaces Air
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Two rigid cells have the same volume and temperature. Each holds ten gas particles in a classroom model. A dry-air particle has a model mass of 29 units, and a water molecule has a mass of 18 units. At this volume and temperature, pressure depends on the total particle count.
| Cell | Dry-air particles | Water molecules |
|---|---|---|
| P | 10 | 0 |
| Q | 6 | 4 |
Question 1
Which comparison of pressures fits the model?
- P has greater pressure.
- Q has greater pressure.
- The pressures are equal.
- Pressure cannot be compared without the particle masses.
Question 2
Calculate and compare the gas masses in the cells.
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Question 3
A student says equal pressures at equal volume and temperature establish equal gas mass. Evaluate the claim with the two cells.
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The model replaces one more dry-air particle in Q with one water molecule while keeping the same volume and temperature. All ten particles remain in the gas phase.
Question 4
Predict how the pressure and gas mass change after the replacement.
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