logK2/K1Â Â = Ea/2.303R * [1/T1 -1/T2]
log0.688/0.0123Â Â = Ea/2.303*8.314 *[1/400 -1/450]
1.7476Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
= Ea/19.1471* [0.0025 -0.0022]
1.7476Â Â Â Â Â Â Â Â Â Â Â Â Â Â
= Ea*0.0003/19.1471
Ea  = 1.7476*19.1471/0.0003 = 111538joules =
111.538Kj
logK2/K1Â Â = Ea/2.303R * [1/T1 -1/T2]
log0.688/K2 = 111538/2.303*8.314 *[1/400 -1/425]
  log0.688/K2     =
111538/19.1471* [0.0025 -0.0023]
                         Â
= 5825*0.0002
                         Â
= 1.165
0.688/K2Â Â Â Â Â Â Â Â Â Â Â
= 101.165
0.688/K2Â Â Â Â Â Â Â Â Â Â Â
= 14.621
K2 = 0.688/14.621 = 0.04705sec-1 >>>>
answer