[Leoonard]

Hi.

I have read alot of the other posts in this forum. And from what i can gather, i will have to plot a ln(rate) against a ln(concentration) graph. But how will that help me get a rate constant? What does the slope represent?

Just to confirm, i find the rate of the reaction by measuring the change in concentration over the time taken for it to take place is it? Rather, i can simply calculate how much mole is produced over a period of time is it?

Once again,the main question is how to get the rate constant of a reaction? Many Thanks!

[Yggdrasil]

It depends on the order of your reaction.  A first order reaction has a rate law:

rate = d[A]/dt = k[A]

Which has the integral form:

[A]_t = [A]_oe^-kt

If you take the log of both sides of the equation:

ln([A]_t) = ln([A]_o) - kt

So, if you plot ln([A]_t) v t, you get a line with y-intercept ln([A]_o) and slope -k.

However, this method applies only for first order reactions.  For reactions that have different rate laws, you need to make different graphs.