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Agent M27
Sep18-10, 03:42 PM
1. The problem statement, all variables and given/known data

A reaction is found to have an activation energy of 38.0 kJ/mol. If the rate constant for this reaction is 1.60 × 102 M-1s-1 at 249 K, what is the rate constant at 436 K?

2. Relevant equations

ln\frac{K_{2}}{K_{1}}=\frac{E_{a}}{R}\left(\frac{1 }{T_{1}}-\frac{1}{T_{2}}\right)

3. The attempt at a solution

Given:

R=8.314
T1=249K
T2=436K
Ea=160

ln(K_{2})=\frac{38}{8.314}\left(\frac{1}{249}-\frac{1}{436}\right)+ln(160)

Which equals 161.257 which is incorrect. Any clues where I went wrong would be greatly appreciated. Thanks in advance.

Joe

Borek
Sep18-10, 03:49 PM
38000

Agent M27
Sep19-10, 11:14 AM
Ah ha! I should have noticed that being that R has units of J not Kj. Thank you very much Borek.

Joe

Borek
Sep19-10, 01:39 PM
kJ, not Kj...