The rate constant of a reaction is 1.5 × 10⁷ s⁻¹ at 50°C and 4.5 × 10⁷ s⁻¹ at 100°C. Evaluate the Arrhenius parameters A and 
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Answers
Answer:
The Arrhenius parameters are as follows
1) Ea=22.01KJ/mol
2) A= 24.7204
Explanation:
The Arrhenius equation is used to calculate Ea that is activation energy.
It can also be used to determine change in temperature when the rate of reaction is constant.
It is directly proportional to the rate of reaction.
The formula for Arrhenius equation is given as follows:
log(K2/K1) = Ea/2.303R (T2-T1/T2T1)
Where
K is rate constant.
Ea is activation enegry.
T is temperature.
Given
rate constant of the reaction =
K1= 1.5 *10^7s⁻¹
T1=50°C = 323K
rate constant of the reaction =
K2= 4.5 * 10⁷ s⁻¹
T2= 100°C= 373K
R= 8.314
To find:
the Arrhenius parameter A and Ea
Using the formula given above
log (4.5*10^7/1.5*10^7)
= Ea/2.303*8.314(373-323/373*323)
log3 =
Ea/2.303*8.314(50/373*323)
Ea= 0.4771*2.303*8.314*373*323/50
=1100636.918/50
=22012.73837 J/mol
=22.01KJ/mol
Also
k= Ae^-Ea/RT
ln k = -Ea/RT+ ln A
ln A = ln k+Ea/RT
= ln(4.5*10^7) + 22012.73/(8.314*373)
= 17.6221+7.0983
=24.7204