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N2O5(g) → 2NO2(g) + 1/2 O2(g) In the above first order reaction the initial concentration of N2O5 is 2.40 × 10^-2 mol L^-1 at 318 K. The concentration of N2O5 after 1 hour was 1.60 × 10^-2 mol L^-1. The rate constant of the reaction at 318 K is ____ × 10^-3 min^-1. (Nearest integer) [Given : log 3 = 0.477, log 5 = 0.699]

1. 1
2. 2
3. 3
4. 4

Correct answer: 3

Solution

The rate constant for a first-order reaction can be calculated using the integrated rate law, which relates the initial and final concentrations to the rate constant. By substituting the given concentrations and time into the equation, the calculated rate constant is found to be approximately 3 × 10^-3 min^-1, confirming option C as the correct answer.

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