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Consider the following first order gas phase reaction at constant temperature A(g) → 2B(g) + C(g) If the total pressure of the gases is found to be 200 torr after 23 sec. and 300 torr upon the complete decomposition of A after a very long time, then the rate constant of the given reaction is _____ × 10^-2 s^-1 (nearest integer) [Given : log10(2) = 0.301]
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- 2
- 3
- 4
Correct answer: 3
Solution
The rate constant can be determined using the change in pressure over time, where the initial pressure of A decreases while the products B and C increase. Given the total pressures at two different times, we can apply the first-order kinetics formula to find that the rate constant is approximately 3 × 10^-2 s^-1.
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