## Half-life of first order reactions

$\frac{d[R]}{dt}=-k[R]; \ln [R]=-kt + \ln [R]_{0}; t_{\frac{1}{2}}=\frac{0.693}{k}$

Nancy Le - 1F
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### Half-life of first order reactions

Is it correct to say that the greater the rate constant, the shorter the half-life is because it doesn't depend on the concentration of reactants?

Julian Krzysiak 2K
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### Re: Half-life of first order reactions

Yup, that is exactly correct!

From the book, "The half-life of a reactant that decays in a first-order reaction is characteristic of the reaction and independent of the initial concentration. It is inversely proportional to the rate constant of the reaction."

Allison Young 1K
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### Re: Half-life of first order reactions

Yes, the half-life decreases as the rate constant increases.

Ya Gao
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### Re: Half-life of first order reactions

Yes and it not only works for first order reactions. It is the case for all reactions.