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Checking Where Dissolved Zinc Came From 5 questions
Checking Where Dissolved Zinc Came From
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A reaction simulation uses a sample containing zinc metal and zinc oxide. Both forms give dissolved Zn2+. Only the metal route also produces hydrogen gas. The simulation collects all hydrogen, records all dissolved zinc ions, and runs both routes to completion.
Zn + 2 H+ → Zn2+ + H2
ZnO + 2 H+ → Zn2+ + H2O
| Record | Amount (mol) |
|---|---|
| Zn2+ in solution | 0.050 |
| H2 collected | 0.020 |
Question 1
Which measurement directly gives the amount of zinc metal that reacted?
- The 0.050 mol Zn²⁺ reading
- The 0.020 mol H₂ reading
- The sum of the two readings
- Neither reading can be used
Question 2
Calculate the amounts of zinc metal and zinc oxide originally present.
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Question 3
A student says all the dissolved zinc came from oxidation of zinc metal. Select whether the evidence supports or refutes the claim. Use oxidation numbers for the oxide route.
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A second model gives the same dissolved zinc reading, but the hydrogen amount doubles.
Question 4
Predict how much of the second sample’s dissolved zinc came from zinc oxide.
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Question 5
Compare how much H⁺ the two samples use. Explain whether a measurement of H⁺ use could distinguish the two starting mixtures.
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