In: Chemistry
a) The activation energy of a certain reaction is 47.0 kJ/mol . At 24 ∘C , the rate constant is 0.0190s−1. At what temperature in degrees Celsius would this reaction go twice as fast?
b)Given that the initial rate constant is 0.0190s−1 at an initial temperature of 24 ∘C , what would the rate constant be at a temperature of 100. ∘C for the same reaction described in Part A?
ln (k2/k1) = (-Ea/R) [(1-T2) - (1/T1)]
k2 / k1 = 2 .
Ea = 47 x 103 joules / mol
T1 = 273 +42 = 315 K
T2 = ?
ln 2 = -47 x 103 / 8.314 [1/T2 - 1/315]
0.6931 = -5.65 x 103 [1/T2 - 1/315]
0.6931 = -5.65 x 103 [1/T2 - 0.00317]
[1/T2 - 0.00317] = -0.6931 / 5.65 x 103
[1/T2 - 0.00317] =- 0.1226 x10-3
1/T2 = 0.00305
T2 = 327
At 327 K or 54 degrees Celsius would this reaction go twice as fast
Question b
ln (k2/k1) = (-Ea/R) [(1-T2) - (1/T1)]
ln k2 / 0.0190 = -47 x 103 / 8.314 [1/373 - 1/297]
ln k2 / 0.0190 =3.878
K2 = 0.9184s−1
K2 = 0.9184 s−1 at a temperature of 100∘C