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A substance 'A' decomposes by a first or der reaction starting initially with [A] = 2.00 m and after 200 min, [A] becomes 0.15 m. For this reaction t1/2 is [1995]
  • a)
    53.72 min
  • b)
    50.49 min
  • c)
    48.45 min
  • d)
    46.45 min
Correct answer is option 'A'. Can you explain this answer?
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A substance 'A' decomposes by a first or der reaction starting...
Given initial concentration (a) = 2.00 m; Time taken (t) = 200 min and final concentration (a – x)    = 0.15 m. For a first order reation rate constant,
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A substance 'A' decomposes by a first or der reaction starting...
Given:
Initial concentration of A, [A]0 = 2.00 M
Concentration of A after 200 min, [A] = 0.15 M

We know that the reaction follows first-order kinetics, which can be represented as:

Rate = k[A]

where k is the rate constant.

To find the half-life of the reaction, we can use the formula:

t1/2 = ln(2)/k

where ln(2) is the natural logarithm of 2.

To find the rate constant, we can use the integrated rate law for a first-order reaction:

ln([A]0/[A]) = kt

Rearranging this equation, we get:

k = ln([A]0/[A])/t

Substituting the given values, we get:

k = ln(2.00/0.15)/200 = 0.0228 min^-1

Substituting this value of k in the formula for t1/2, we get:

t1/2 = ln(2)/0.0228 = 53.72 min

Therefore, the correct answer is option A, 53.72 min.
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A substance 'A' decomposes by a first or der reaction starting initially with [A] = 2.00 m and after 200 min, [A] becomes 0.15 m. For this reaction t1/2 is [1995]a)53.72 minb)50.49 minc)48.45 mind)46.45 minCorrect answer is option 'A'. Can you explain this answer?
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A substance 'A' decomposes by a first or der reaction starting initially with [A] = 2.00 m and after 200 min, [A] becomes 0.15 m. For this reaction t1/2 is [1995]a)53.72 minb)50.49 minc)48.45 mind)46.45 minCorrect answer is option 'A'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about A substance 'A' decomposes by a first or der reaction starting initially with [A] = 2.00 m and after 200 min, [A] becomes 0.15 m. For this reaction t1/2 is [1995]a)53.72 minb)50.49 minc)48.45 mind)46.45 minCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A substance 'A' decomposes by a first or der reaction starting initially with [A] = 2.00 m and after 200 min, [A] becomes 0.15 m. For this reaction t1/2 is [1995]a)53.72 minb)50.49 minc)48.45 mind)46.45 minCorrect answer is option 'A'. Can you explain this answer?.
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