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### Topic: quick question  (Read 4264 times)

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#### zeshkani

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##### quick question
« on: January 25, 2008, 06:32:17 PM »
When you have a second oder reaction
A + B --> C

and your are given both the initial concentration of A and B
and to find the half-life of both A and B would you just use this question t1/2=1/k[A or B]o
iam using this question but i just dont think its this simple,

is there something more to this equation, or i just used it the way it is

#### Kryolith

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##### Re: quick question
« Reply #1 on: January 25, 2008, 06:38:24 PM »
You are right. It is that simple

2 A ----> B

$v=k*[A]^2$

$[A]=\frac{[A]_0}{1+k*t*[A]_0}$

$t_{1/2}=\frac{1}{k*[A]_0}$

#### zeshkani

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##### Re: quick question
« Reply #2 on: January 26, 2008, 12:45:25 PM »
but when we calculated the half life
of this ex:
A + 2B --->  P

we used this equation: t1/2= 1/k*1/(B-2)(A)*Ln(A(B-2)(A/2))/(A-(A/2))(B)

so thats why iam still confused, and this one looks alot different then from the normal second order half life equation
« Last Edit: January 26, 2008, 01:23:48 PM by zeshkani »