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Consider the following parallel reactions being given by A (t 1/2 = 1.386 × 10 2 hours), each path being 1 st order. If distribution of A in the product mixture is 50%, calculate partial half-life of A for the conversion into B.

Options

  1. A346.5 h
  2. B231 h
  3. C154 h
  4. D92.4 h

Correct answer

B. 231 h

Step-by-step solution

From question 2 k 1 2 k 1 + 3 k 2 = 0.5 and k 1 + k 2 = 0.693 1.386 × 1 0 2 = 5 × 1 0 - 3 h -1 Solving k 1 k 2 = 3 2 and k 1 = 3 × 1 0 - 3 h -1 and k 2 = 2 × 1 0 - 3 h -1 t 1 / 2 A → B = 0.693 k 1 = 0.693 3 × 1 0 - 3 = 2 3 1 h

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