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Reaction A(g) → 2B(g) + C(g) is a first order reaction. It was started with pure A. t/min | Pressure of system at time t/mm Hg 10 | 160 ∞ | 240 Which of the following option is incorrect?

1. (1) Partial pressure of A after 10 minute is 40 mm Hg
2. (2) Initial pressure of A is 80 mm Hg
3. (3) The reaction never goes to completion
4. (4) Rate constant of the reaction is 1.693 min^-1

Correct answer: (4) Rate constant of the reaction is 1.693 min^-1

Solution

The rate constant for a first-order reaction is calculated using the formula k = (1/t) * ln(P0/P), where P0 is the initial pressure and P is the pressure at time t. Given the pressures, the calculated rate constant does not equal 1.693 min^-1, making this option incorrect.

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