Is half life for first order is depend on the stochiometric coefficient of reactant or product? [closed]








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I took k=6.93x10^(-2) as given in ques and use the half life formula for 1st order kinetics and solve and finally get 10 min as a ans but right ans is 5 min and i m not able to get that..... Plse tell where i m doing mistake?? 




If the reaction has the form $aA \rightarrow B + C $ then the rate at which *B* and *C* are produced is $1/a$ of the rate at which A disappears, thus
$$ -\frac{1}{a}\frac{dA}{dt}= \frac{dB}{dt}= \frac{dC}{dt}=kA$$


On this basis the half-life should be $5$ minutes in your question.


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