A well-known aphorism in chemistry is that for every 10° increase in temperature

Question

A well-known aphorism in chemistry is that for every 10° increase in temperature, the rate of a reaction will increase twofold. If the reaction were performed at 45° C predict whether it would occur at twice the rate of the reaction performed at 35° C (Show relevant calculations to confirm your answer. If your second set of kinetic trials was performed at a temperature other than 35°, use a temperature exactly 10° higher for the calculation, for example if your second set of trials was run at 38° C, compare 38° to 48°C.

Comparing T2= 33°C with T= 43°C: when Ea= 42.238 KJ/mol

At 33°C: K33 = e[(Ea/0.008314 KJ mol-K-)(1/306.15 K)] = 6.21E-8

At 43°C: K43 = e[(Ea/0.008314 KJ mol-K-)(1/316.15 K)] = 1.05E-7

K43/K33 = 1.691 ~2.00

If A=Ea remains the same after increasing doubling the temperature, the rate of reaction increases as temperature increases.

Can somebody check my answer?

Explanation / Answer

Comparing T1= 33°C with T2= 43°C: when Ea= 42.238 KJ/mol

K1 = A e (-Ea/RT1)

K2 = A e (-Ea/RT2)

lnK2/K1 = Ea/R (1/T1 -1/T2) = 42.238 x 1000 J/mol ¸ 8.314 J/Kmol (1/306 K – 1/316 K)

log K2/K1 =1/2.303 [42.238 x 1000 J/mol ¸ 8.314 J/Kmol (1/306 K – 1/316 K)]

= 0.238

K1/K2 = antilog 0.238 = 1.72 ~2.00

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