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Tracking a Reagent Returned in Step Two 4 questions
Tracking a Reagent Returned in Step Two
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A process model uses U and V to form an intermediate W. Each W contains two U units and one V unit. The second step converts each W into one Z unit containing both U units and returns the V unit unchanged. Returned V can be used again. The process has no losses or other changes.
2 U + V → W
W → Z + V
| Quantity at the start | Count (model units) |
|---|---|
| U | 12 |
| V | 3 |
Question 1
How many W units can form in the first pass before any V is returned?
- Three
- Six
- Nine
- Twelve
Question 2
Find how many U units remain and how many V units are available after the first W units complete the second step.
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Question 3
A student says the display can produce no more than three Z units from the starting amounts. Use the two reactions to determine the maximum number of Z units.
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A repeat starts with the same 12 U units but only two V units. It runs each pass to the limit and returns all available V before the next pass.
Question 4
Find how many complete passes are needed to turn all the U into Z and how much V remains when finished.
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