## Half life constant and Rate reaction constant

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

Ardo 2K
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### Half life constant and Rate reaction constant

When we find the constant K for a reaction from the half life equation can we apply that same constant to the second order reaction equation to find the concentration of a given reactant?

Ozhen Atoyan 1F
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### Re: Half life constant and Rate reaction constant

If you use the second order half life formula then you can use that k in the second order reaction to find the concentration. There are different half life formulas depending on if its zero, first, or second order.

Luis De La Cruz 1H
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Joined: Fri Sep 25, 2015 3:00 am

### Re: Half life constant and Rate reaction constant

Like stated above, each K constant that you derive will be different, depending on the order of the reaction (0,1, or 2) because each order has its own half life formula associated with it.

DamianW
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Joined: Fri Sep 29, 2017 7:06 am

### Re: Half life constant and Rate reaction constant

So order does matter ?

Phi Phi Do 2E
Posts: 27
Joined: Fri Sep 29, 2017 7:05 am

### Re: Half life constant and Rate reaction constant

yes, order does matter when you are solving for k. That is why the units differ for the k value in each rate order.