1. The problem statement, all variables and given/known data For a reaction, A + H2O --> B + C We're given that d[A]/dt = k[A]n[H3O+]m And also a table of [A] vs time at T1 and pH 1, pH 2; as well as [A] vs time at T2 and the same pH 1 and 2. From this data, we're to find pseudo-n-order rate constants, and then n itself. Next, the activation energy at each pH, and then the value of k at each temperature. Finally, we need the activation energy for the overall reaction. 3. The attempt at a solution I'm not really familiar with this kind of problem, unfortunately. I started by plotting ln[A] vs. time, and got a straight line, from which I concluded that it was 1st order relative to [A]. I found the slopes of each of these 4 lines (T1, pH 1; T1, pH 2; etc), and I determined that the negative of each of these was the pseudo-n-order constants. That was the first two parts. I was also able to find the activation energy for each pH, by using the formula ln(k2/k1) = Ea(1/T2 - 1/T1). I used the two pseudo equation k values at each temperature to calculate these, and got 2 activation energy values, which were about 1000 J off from each other. Here's where I'm stuck. I can't think of any way to go about calculating k for each temperature. I thought about using k = Ae-Ea/RT, but I don't know A, for one, and the activation energies I just calculated are separate for each pH, not temperature, so that doesn't help me much either. Thanks for any help.