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If the time required for a reaction to be half complete is inversely proportional to the initial concentration of the reactant, what is the order of the reaction?

1. Zero
2. 1
3. 2
4. 3

Correct answer: 2

Solution

Since t1/2 is proportional to a^(1-n) and here t1/2 is proportional to 1/a, we get 1-n = -1, so n = 2.

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