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Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: zeshkani on January 25, 2008, 06:32:17 PM

Title: quick question
Post by: zeshkani 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 t_1/2=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 ???

Title: Re: quick question
Post by: Kryolith on January 25, 2008, 06:38:24 PM

You are right. It is that simple  ;)

2 A ----> B

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Title: Re: quick question
Post by: zeshkani 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: t_1/2= 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