Practice Half-life Of A Reaction (3.3.3) - Chemical kinetics

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6 sample questions

Question 1.
Define half-life in your own words.
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Think about it as time related to decay.
Question 2.
What is the half-life formula for a first-order reaction?
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Recall the specific variable associated with first-order kinetics.
3Question 3.
What is the half-life of a first-order reaction?
- Depends on initial concentration
- Constant regardless of concentration
- Decreases with time
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Think about how a reaction behaves as it progresses.
4Question 4.
True or False: For zero-order reactions, half-life decreases as reactant concentration decreases.
- True
- False
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Consider the implications of the zero-order definition.
Question 5.
A first-order reaction has a rate constant of 0.5 h-1. How much of the reactant is left after 4 hours if you start with 1 mole?
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Use the half-life formula and calculate the fraction remaining after each half-life period.
Question 6.
For a zero-order reaction where k = 0.1 M/s and the initial concentration is 1 M, calculate the concentration after 20 seconds.
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Consider how zero-order dependencies work over time.

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