C3H6 (g) ------> CH3CH=CH2 (g)
rate law
rate = K[C3H6]1
t    = 20min = 20*60 = 1200sec
K = 2.303/t log[A0]/[A]
6.7*10-4 = 2.303/1200 log0.1/[A]
log0.1/[A]Â Â = 6.7*10-4 *1200/2.303
                 Â
= 3491.1*10-4
log0.1/[A]Â Â Â = 0.34911
   0.1/[A]   =
100.34911
   0.1/[A]   = 2.2341
       Â
[A]Â Â Â = 0.1/2.2341 = 0.04476M
3. 2 C4H6 (g) ----> C8H12
(l)
     rate =
k[C4H6]2Â Â
K = 1/t [1/[A0] -1/[A]
t  = 1/K [1/[A] -1/[A0] ]
   = 1/4*10-2 [1/0.04 -1/0.2]
    =25*(25-5)
    = 500sec
4. no of half live = total time/half life time
            Â
3
          Â
= 1200/half live time
           Â
half life time = 1200/3 = 400sec
b. 1 = total time /400
  time = 400sec
   2  = total time/400
  time  = 800sec