Determine Activation Energy from rate?

1. Nov 24, 2011

jtruth914

On my test the professor gave us the rate, parameters of A, and temperature of 298K. We were asked to find the activation energy. I know that the Arrhenius equation is LnK= LnA-Ea/RT. However, he did not give us the rate constant "K" instead he gave us the rate. How do you determine activation energy using the rate.

2. Nov 25, 2011

Ygggdrasil

Did he tell you the reaction, the concentration of reactants, and the rate law?

3. Nov 25, 2011

jtruth914

No he didn't. I assumed it was a zeroth order reaction where k=rate. Even though he didn't specify that. That's what confused me.