A calculate the half-life of the reaction at 726c based on

Question

The reaction C₂H₅CN(g)-----> CH₂CHCN(g) +H₂(g) is first order. In an experiment, the rate constant is determined to be 0.148 s^-1 at 726°C.

(a) Calculate the half-life of the reaction at 726°C based on this experiment.

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(b) If the initial partial pressure of C₂H₅CN in a container at 726°C is 2.64 atm, how long will it take to fall to 0.330 atm?

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