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Following Iron Ions Through a Color Cycle 4 questions
Following Iron Ions Through a Color Cycle
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A simulation represents a closed solution containing Fe2+ and Fe3+. Its indicator reading increases when the amount of Fe3+ increases. Students track the iron ions during two steps. The total iron stays dissolved and the only iron change is between these two ions.
| Stage | Fe2+ amount (mmol) | Fe3+ amount (mmol) |
|---|---|---|
| Start | 8.0 | 2.0 |
| After step 1 | 3.0 | 7.0 |
| After step 2 | 6.0 | 4.0 |
Question 1
Which description fits the iron change during step 1?
- Fe³⁺ gains electrons and becomes Fe²⁺.
- Fe²⁺ loses electrons and becomes Fe³⁺.
- Fe²⁺ gains protons and becomes Fe³⁺.
- Fe³⁺ loses protons and becomes Fe²⁺.
Question 2
Calculate the amount of electrons accepted by the iron ions during step 2. Show how the ion count changes enter the result.
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The indicator reading remains above its starting value after step 2. A student claims that more iron entered the solution.
Question 3
Use the table to explain why the indicator can stay above its starting value while the total iron amount stays the same.
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Question 4
What change to the remaining Fe³⁺ would restore both original amounts? State the direction of electron transfer and how much iron must change.
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