[mol]

C3H6O  +I2  -------> C3H6OI   + H+   + I-


acetone M           H+ M           I2 M              rate of rctn M/sec

.100                   .100             .100               2.6 *10^-7

.100                   .100             .200               2.6* 10^-7

.100                    .200           .400                5.2* 10^-6

.200                     .200           .400               1.0* 10^-5




To fidn the order of the reaction of each chemical species above, I found that
rate2/rate1 for Iodine is zero order. becoz x =o

but for acetone and H+ I am not getting any whole no values.
For acetone I got    2power y = .2    and for H+  iam getting .5 power x 1.9


I am applying the rate 2/rate 1 formula just like I did  for iodine but why am I not getting whole nos for acetone and H+?
I am not sure where I am getting it wrong.. I am totally confused.. pls help. I went through the search criteria in this forum to find out a previous post similar to this problem and I found that my formula n approach were right..

[DevaDevil]

well, let's start at the beginning; the reaction is not balanced for one, typo?

anyway, you are right about 0 order for iodine: when increasing iodine concentration there is no change in the reaction rate

the order in acetone:
compare the last 2 values, doubling of acetone gives a doubling of the reaction rate, so the order is 1. ( r = k₁ * [acetone]¹ = k₂ * [H⁺]ⁿ, directly proportional to the amount of acetone)

I am surprised about the rate change in a change of proton concentration, as when the concentration of acetone stays the same (and iodine is 0 order), then the rate should not change
Then compare the 2 middle values where only the concentration of protons is changing. This will give you the rate in H⁺

[mol]

Thanks DevaDevil .your reply was pretty clear .Yup I got it now.