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Reading a Steady Reactant in a Flow Model 4 questions
Reading a Steady Reactant in a Flow Model
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A classroom flow model feeds dissolved reactant R into a vessel. The feed adds R particles without an appreciable change to the volume. The reaction turns one R particle into one product particle. The feed and reaction are the only changes to the amount of R in this model.
| Interval | R entering per second | R used per second | Amount of R at end |
|---|---|---|---|
| First 10 s | 4 | 2 | 60 |
| Next 10 s | 4 | 4 | 60 |
Question 1
Which statement describes the balance of R during the second interval?
- R stops entering and stops reacting.
- R enters faster than it reacts.
- R reacts faster than it enters.
- R enters and reacts at equal rates.
Question 2
Calculate the increase in the amount of R during the first ten seconds.
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Question 3
A student says the unchanged amount of R proves that no product forms during the second interval. Use the records to evaluate the claim.
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The feed is then turned off. For the first two seconds after that change the reaction still uses four R particles per second.
Question 4
Calculate the amount of R after those two seconds. Explain why the reading now changes.
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