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A → B The molecule A changes into its isomeric form B by following a first order kinetics at a temperature of 1000 K. If the energy barrier with respect to reactant energy for such isomeric transformation is 191.48 kJ mol−1 and the frequency factor is 10^20, the time required for 50%, molecules of A to become B is ________ picoseconds (nearest integer). [R = 8.314 J K−1 mol−1]
- 69
- 693
- 6.93
- 6930
Correct answer: 69
Solution
The time required for 50% of the molecules to transform in a first-order reaction can be calculated using the formula for half-life, which is dependent on the rate constant. Given the activation energy and frequency factor, the rate constant can be determined using the Arrhenius equation, leading to a calculated half-life of approximately 69 picoseconds.
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