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Reading a Reaction After a Sample Is Removed 4 questions

Reading a Reaction After a Sample Is Removed

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A model vessel forms product B. Its detector reports the number of B units still in the vessel. At 10 seconds a sampler withdraws a portion of liquid and records the detector reading just before and just after. The withdrawal is effectively instantaneous. Outside that moment B stays in the vessel as it forms.

Graph of product B in the vessel. The reading is zero at 0 seconds, ten just before the withdrawal at 10 seconds, six just after it, and fourteen at 20 seconds.
Detector readings before and after a liquid sample is withdrawn.
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Question 1

How many B units does the sampler remove?

  1. Four
  2. Six
  3. Ten
  4. Fourteen

Question 2

Calculate the average rate of B formation before the withdrawal and over the ten seconds after it.

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Question 3

A student says the drop at 10 seconds proves that B reacted away. Evaluate the claim with the measurement procedure.

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The sampler keeps all of its withdrawn liquid for a separate analysis. The vessel is stopped after the 20-second reading.

Question 4

Calculate how much B formed over the whole run. Include the product in both locations.

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