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Finding Which Step Delays a Color Change 4 questions
Finding Which Step Delays a Color Change
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A color display changes a colorless model particle A into blue particle B, then changes B into colorless particle C. Each step converts one particle to one particle. Trials P and Q both start with ten A particles and no B or C. Q contains an added material. All other conditions match.
| Trial | A at the early check | B at the early check | C at the early check |
|---|---|---|---|
| P | 6 | 1 | 3 |
| Q | 2 | 5 | 3 |
Question 1
Which early observation shows more buildup of the blue intermediate?
- P has one B particle while Q has five.
- P has six A particles while Q has two.
- Both trials have three C particles.
- Both trials began with ten A particles.
Question 2
Calculate how many particles passed through the first step in each trial by the early check. Use the A counts.
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Two matched follow-up trials start with ten B particles and no A or C. With or without the added material, the measured B and C records match over the entire observation period.
Question 3
Explain how starting with B helps test whether the added material changes the second step.
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Question 4
At the final check both original trials contain ten C particles. Use the early and final records to evaluate the claim that the added material increases final product yield.
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