The rate constant for the decomposition of hydrocarbons is `2.418xx10^(-5)s^(-1)` at `546K`. If the energy of activation is `179.9kJ mol^(-1)`, what will be the value of pre`-`exponential factor?
Text Solution
Verified by Experts
`k=2.418xx10^(-5)s^(-1)` ` T = 546 k ` `E_(a)=179.9KJ mol^(-1) =179.9xx10^(3) J mol ^(-1)` According to the Arrhenius equation, `k=Ae^(-E)` `rArr "In "k=In A-E_(0)/(RT)` `rArr"log"k=log A-E_(0)/(2.303RT)` `rArr"log"A=log K+E_(0)/(2.303RT)` `="log"(2.418xx10^(-5)S^(-1))+(179.xx10^(3) J "mol"^(-1))/(2.303xx8.314 "JK"^(-1)"mol"^(-1)xx546K)` =`(0.3835 - 5) + 17.2082` 12.5917 Therefore, A = antilog `(12.5917)` `= 3.9 × 10^(12) s^(−1)` (approximately)
Topper's Solved these Questions
CHEMICAL KINETICS
NCERT|Exercise Exercise|1 Videos
CHEMICAL KINETICS
NCERT|Exercise SOLVED EXAMPLE|1 Videos
BIOMOLECULES
NCERT|Exercise Exercise|33 Videos
CHEMISTRY IN EVERYDAY LIFE
NCERT|Exercise Exercise|32 Videos
Similar Questions
Explore conceptually related problems
The decomposition of methyl iodid, 2CH_(3)I(g)rarrC_(2)H_(6)(g)+I_(2)(g) at 273^(@) C has a rate constant of 2.418xx10^(-5)s^(-1) . If activation energy for the reaction is +179.9 kJ "mol"^(-1) , what is the value of collision factor A at 273^(@)C ?
The specific rate constant for the decomposition of formic acid is 5.5xx10^(-4) sec^(-1) at 413 K . Calculate the specific rate constant at 458K if the energy of activation is 2.37xx10^(4) cal "mol"^(-1)
The first order rate constant for the decomposition of CaCO_3 , at 700 K is 6.36 xx 10^(-3)s^(-1) and activation energy is 209 "kJ mol"^(-1) . Its rate constant (in s^(-1) ) at 600 K is "x" xx 10^(-6) . The value of x is ______ .(Nearest integer) [Given R=8.31 J K^(-1) "mol"^(-1) , log 6.36 xx 10^(-3)= -2.19, 10^(-4.79)= 1.62 xx10^(-5) ]