## half life

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

Ekayana Sethi 2K
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### half life

What does n half lives mean?

Dylan Davisson 2B
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### Re: half life

"n" half lives just refers to how many half lives have occurred at any stage of the reaction in question. A half life occurs at the specific time when the current value of the concentration of reactants is halved. For example, after 2 half lives (n=2), the concentration of the reactants would be 1/4 the original concentration (1/2 * 1/2). After three half lives (n=3), the concentration of the reactants would be 1/8 the original concentration ( 1/2 * 1/2 * 1/2).

Allison Young 1K
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### Re: half life

A half-life is like a unit of time. For example, if the half-life of something is 2 hours, then 3 half-lives would be 6 hours. After that point 1/8th of the reactant would be left.

Abby Ellstrom 1I
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### Re: half life

'n' half lives refer to how many times the concentration has been halved at that point.