2 The following plots show kinetic data for a reaction of th

2. The following plots show kinetic data for a reaction of the form A P a. Plots of [A], In[A] vs t and 1/IA] vs t are shown below. Can you determine the reaction order in [A] from either of these plots? Can you determine the rate constant? 0.00012 0.0001 0.00008 0.00006 0.00004 Concentration Data 9.5 10 -10.5 y =-0.8308x-9.2032 R2 = 0.997 18 .s2 -12.5 13 -13.5 Time(s) Time(s) 1200000 y 107040x- 111087 R2 0.74555 2 800000 600000 400000 200000 Time(s) tid

Solution

ln A vs time gave straight line

hence we had 1st order

formula for 1st order kinectis is t = ( 1/k) ln ( [Ao] / [At]

which can be reaaranged as t = ( -1/k) ln [At] + ( ln [Ao] / k)

this is form y= mx + c where m = slope = -1/k

in our 2nd graph y = - 0.8308x - 9.2032

hence slope = - 0.8308 = - 1/k

k = 1/0.8308 = 1.2 s-1 ( rate constant will have units of time -1)

hence reatcion order is 1

rate constant = 1.2 s-1