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The half-life period of a first-order reaction is 15 minutes . The amount of substance left after one hour will be

Options

  1. A1 1 6 of the original amount
  2. B1 8 of the original amount.
  3. C1 3 2 of the original amount.
  4. D1 4 of the original amount.

Correct answer

A. 1 1 6 of the original amount

Step-by-step solution

For the first-order reaction A   →   Product [ A ] t = [ A 0 ]   1 2 Δt t 1 / 2 [ A ] t = A 0 1 2 60 15 = A 0 1 2 4 ∴ [A] t = A 0 16

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