Catalysts in industry
2 marks · EasyIn an experiment, two reactions are compared: one with a catalyst and one without. The time for the reaction without a catalyst is 30 minutes. With a catalyst, the same reaction takes 10 minutes. If a student wants to show the substance is a catalyst, what further step should she take besides measuring the rates? Explain your answer.
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She should show that the substance can be recovered unchanged at the end of the reaction and can still function as a catalyst.
Also accept: Prove that the substance can be separated at the end and reused in a new experiment.
Common mistakes: Only mentioning that it increased the reaction rate.
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Marking points
M1 · 1 mark · Identifies that the substance must be recovered at the end of the reaction.
M2 · 1 mark · Explains that the substance must be chemically unchanged and able to catalyse the reaction again.
Worked solution
She should collect the substance after the reaction and check that it is unchanged. She could use it in another reaction to see if it still speeds up the process.